item.cc 161 KB
Newer Older
unknown's avatar
unknown committed
1
/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
unknown's avatar
unknown committed
2

unknown's avatar
unknown committed
3 4 5 6
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
unknown's avatar
unknown committed
7

unknown's avatar
unknown committed
8 9 10 11
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
unknown's avatar
unknown committed
12

unknown's avatar
unknown committed
13 14 15 16 17
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */


18
#ifdef USE_PRAGMA_IMPLEMENTATION
unknown's avatar
unknown committed
19 20 21 22 23
#pragma implementation				// gcc: Class implementation
#endif
#include "mysql_priv.h"
#include <m_ctype.h>
#include "my_dir.h"
24
#include "sp_rcontext.h"
25 26
#include "sp_head.h"
#include "sql_trigger.h"
27
#include "sql_select.h"
unknown's avatar
unknown committed
28

29 30
static void mark_as_dependent(THD *thd,
			      SELECT_LEX *last, SELECT_LEX *current,
unknown's avatar
unknown committed
31 32
			      Item_ident *item);

33 34
const String my_null_string("NULL", 4, default_charset_info);

35 36 37 38 39 40 41 42 43 44
/****************************************************************************/

/* Hybrid_type_traits {_real} */

void Hybrid_type_traits::fix_length_and_dec(Item *item, Item *arg) const
{
  item->decimals= NOT_FIXED_DEC;
  item->max_length= item->float_length(arg->decimals);
}

unknown's avatar
unknown committed
45
static const Hybrid_type_traits real_traits_instance;
46 47 48

const Hybrid_type_traits *Hybrid_type_traits::instance()
{
unknown's avatar
unknown committed
49
  return &real_traits_instance;
50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68
}


my_decimal *
Hybrid_type_traits::val_decimal(Hybrid_type *val, my_decimal *to) const
{
  double2my_decimal(E_DEC_FATAL_ERROR, val->real, val->dec_buf);
  return val->dec_buf;
}


String *
Hybrid_type_traits::val_str(Hybrid_type *val, String *to, uint8 decimals) const
{
  to->set(val->real, decimals, &my_charset_bin);
  return to;
}

/* Hybrid_type_traits_decimal */
unknown's avatar
unknown committed
69
static const Hybrid_type_traits_decimal decimal_traits_instance;
70 71 72

const Hybrid_type_traits_decimal *Hybrid_type_traits_decimal::instance()
{
unknown's avatar
unknown committed
73
  return &decimal_traits_instance;
74 75 76 77 78 79 80 81
}


void
Hybrid_type_traits_decimal::fix_length_and_dec(Item *item, Item *arg) const
{
  item->decimals= arg->decimals;
  item->max_length= min(arg->max_length + DECIMAL_LONGLONG_DIGITS,
unknown's avatar
unknown committed
82
                        DECIMAL_MAX_STR_LENGTH);
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144
}


void Hybrid_type_traits_decimal::set_zero(Hybrid_type *val) const
{
  my_decimal_set_zero(&val->dec_buf[0]);
  val->used_dec_buf_no= 0;
}


void Hybrid_type_traits_decimal::add(Hybrid_type *val, Field *f) const
{
  my_decimal_add(E_DEC_FATAL_ERROR,
                 &val->dec_buf[val->used_dec_buf_no ^ 1],
                 &val->dec_buf[val->used_dec_buf_no],
                 f->val_decimal(&val->dec_buf[2]));
  val->used_dec_buf_no^= 1;
}


void Hybrid_type_traits_decimal::div(Hybrid_type *val, ulonglong u) const
{
  int2my_decimal(E_DEC_FATAL_ERROR, u, TRUE, &val->dec_buf[2]);
  /* XXX: what is '4' for scale? */
  my_decimal_div(E_DEC_FATAL_ERROR,
                 &val->dec_buf[val->used_dec_buf_no ^ 1],
                 &val->dec_buf[val->used_dec_buf_no],
                 &val->dec_buf[2], 4);
  val->used_dec_buf_no^= 1;
}


longlong
Hybrid_type_traits_decimal::val_int(Hybrid_type *val, bool unsigned_flag) const
{
  longlong result;
  my_decimal2int(E_DEC_FATAL_ERROR, &val->dec_buf[val->used_dec_buf_no],
                 unsigned_flag, &result);
  return result;
}


double
Hybrid_type_traits_decimal::val_real(Hybrid_type *val) const
{
  my_decimal2double(E_DEC_FATAL_ERROR, &val->dec_buf[val->used_dec_buf_no],
                    &val->real);
  return val->real;
}


String *
Hybrid_type_traits_decimal::val_str(Hybrid_type *val, String *to,
                                    uint8 decimals) const
{
  my_decimal_round(E_DEC_FATAL_ERROR, &val->dec_buf[val->used_dec_buf_no],
                   decimals, FALSE, &val->dec_buf[2]);
  my_decimal2string(E_DEC_FATAL_ERROR, &val->dec_buf[2], 0, 0, 0, to);
  return to;
}

/* Hybrid_type_traits_integer */
unknown's avatar
unknown committed
145
static const Hybrid_type_traits_integer integer_traits_instance;
146 147 148

const Hybrid_type_traits_integer *Hybrid_type_traits_integer::instance()
{
unknown's avatar
unknown committed
149
  return &integer_traits_instance;
150 151 152 153 154 155 156 157 158 159
}

void
Hybrid_type_traits_integer::fix_length_and_dec(Item *item, Item *arg) const
{
  item->decimals= 0;
  item->max_length= 21;
  item->unsigned_flag= 0;
}

unknown's avatar
unknown committed
160 161 162 163 164 165 166 167 168 169 170
/*****************************************************************************
** Item functions
*****************************************************************************/

/* Init all special items */

void item_init(void)
{
  item_user_lock_init();
}

unknown's avatar
unknown committed
171 172 173 174

/*
TODO: make this functions class dependent
*/
175

unknown's avatar
unknown committed
176 177
bool Item::val_bool()
{
178
  switch(result_type()) {
unknown's avatar
unknown committed
179
  case INT_RESULT:
180
    return val_int() != 0;
unknown's avatar
unknown committed
181 182 183 184 185 186 187 188 189 190 191 192 193 194
  case DECIMAL_RESULT:
  {
    my_decimal decimal_value;
    my_decimal *val= val_decimal(&decimal_value);
    if (val)
      return !my_decimal_is_zero(val);
    return 0;
  }
  case REAL_RESULT:
  case STRING_RESULT:
    return val_real() != 0.0;
  case ROW_RESULT:
  default:
    DBUG_ASSERT(0);
195
    return 0;                                   // Wrong (but safe)
unknown's avatar
unknown committed
196 197 198 199
  }
}


200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261
String *Item::val_string_from_real(String *str)
{
  double nr= val_real();
  if (null_value)
    return 0;					/* purecov: inspected */
  str->set(nr,decimals, &my_charset_bin);
  return str;
}


String *Item::val_string_from_int(String *str)
{
  longlong nr= val_int();
  if (null_value)
    return 0;
  if (unsigned_flag)
    str->set((ulonglong) nr, &my_charset_bin);
  else
    str->set(nr, &my_charset_bin);
  return str;
}


String *Item::val_string_from_decimal(String *str)
{
  my_decimal dec_buf, *dec= val_decimal(&dec_buf);
  if (null_value)
    return 0;
  my_decimal_round(E_DEC_FATAL_ERROR, dec, decimals, FALSE, &dec_buf);
  my_decimal2string(E_DEC_FATAL_ERROR, &dec_buf, 0, 0, 0, str);
  return str;
}


my_decimal *Item::val_decimal_from_real(my_decimal *decimal_value)
{
  double nr= val_real();
  if (null_value)
    return 0;
  double2my_decimal(E_DEC_FATAL_ERROR, nr, decimal_value);
  return (decimal_value);
}


my_decimal *Item::val_decimal_from_int(my_decimal *decimal_value)
{
  longlong nr= val_int();
  if (null_value)
    return 0;
  int2my_decimal(E_DEC_FATAL_ERROR, nr, unsigned_flag, decimal_value);
  return decimal_value;
}


my_decimal *Item::val_decimal_from_string(my_decimal *decimal_value)
{
  String *res;
  char *end_ptr;
  if (!(res= val_str(&str_value)))
    return 0;                                   // NULL or EOM

  end_ptr= (char*) res->ptr()+ res->length();
262 263 264 265 266 267 268 269 270
  if (str2my_decimal(E_DEC_FATAL_ERROR & ~E_DEC_BAD_NUM,
                     res->ptr(), res->length(), res->charset(),
                     decimal_value) & E_DEC_BAD_NUM)
  {
    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
                        ER_TRUNCATED_WRONG_VALUE,
                        ER(ER_TRUNCATED_WRONG_VALUE), "DECIMAL",
                        str_value.c_ptr());
  }
271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298
  return decimal_value;
}


double Item::val_real_from_decimal()
{
  /* Note that fix_fields may not be called for Item_avg_field items */
  double result;
  my_decimal value_buff, *dec_val= val_decimal(&value_buff);
  if (null_value)
    return 0.0;
  my_decimal2double(E_DEC_FATAL_ERROR, dec_val, &result);
  return result;
}


longlong Item::val_int_from_decimal()
{
  /* Note that fix_fields may not be called for Item_avg_field items */
  longlong result;
  my_decimal value, *dec_val= val_decimal(&value);
  if (null_value)
    return 0;
  my_decimal2int(E_DEC_FATAL_ERROR, dec_val, unsigned_flag, &result);
  return result;
}


299
Item::Item():
300
  rsize(0), name(0), orig_name(0), name_length(0), fixed(0),
301
  is_autogenerated_name(TRUE),
unknown's avatar
unknown committed
302
  collation(&my_charset_bin, DERIVATION_COERCIBLE)
unknown's avatar
unknown committed
303
{
304
  marker= 0;
305
  maybe_null=null_value=with_sum_func=unsigned_flag=0;
306
  decimals= 0; max_length= 0;
307 308 309

  /* Put item in free list so that we can free all items at end */
  THD *thd= current_thd;
310 311
  next= thd->free_list;
  thd->free_list= this;
312
  /*
313
    Item constructor can be called during execution other then SQL_COM
314
    command => we should check thd->lex->current_select on zero (thd->lex
unknown's avatar
unknown committed
315
    can be uninitialised)
316
  */
unknown's avatar
unknown committed
317
  if (thd->lex->current_select)
318
  {
319
    enum_parsing_place place= 
unknown's avatar
unknown committed
320
      thd->lex->current_select->parsing_place;
321 322
    if (place == SELECT_LIST ||
	place == IN_HAVING)
unknown's avatar
unknown committed
323
      thd->lex->current_select->select_n_having_items++;
324
  }
unknown's avatar
unknown committed
325 326
}

327
/*
unknown's avatar
unknown committed
328
  Constructor used by Item_field, Item_*_ref & aggregate (sum) functions.
329 330 331
  Used for duplicating lists in processing queries with temporary
  tables
*/
332
Item::Item(THD *thd, Item *item):
333
  rsize(0),
334 335
  str_value(item->str_value),
  name(item->name),
336
  orig_name(item->orig_name),
337 338 339 340 341 342 343 344
  max_length(item->max_length),
  marker(item->marker),
  decimals(item->decimals),
  maybe_null(item->maybe_null),
  null_value(item->null_value),
  unsigned_flag(item->unsigned_flag),
  with_sum_func(item->with_sum_func),
  fixed(item->fixed),
unknown's avatar
unknown committed
345
  collation(item->collation)
346
{
347 348
  next= thd->free_list;				// Put in free list
  thd->free_list= this;
349 350
}

unknown's avatar
unknown committed
351

unknown's avatar
unknown committed
352 353 354 355 356 357 358 359 360 361 362
uint Item::decimal_precision() const
{
  Item_result restype= result_type();

  if ((restype == DECIMAL_RESULT) || (restype == INT_RESULT))
    return min(my_decimal_length_to_precision(max_length, decimals, unsigned_flag),
               DECIMAL_MAX_PRECISION);
  return min(max_length, DECIMAL_MAX_PRECISION);
}


unknown's avatar
unknown committed
363 364 365 366 367
void Item::print_item_w_name(String *str)
{
  print(str);
  if (name)
  {
368
    THD *thd= current_thd;
369
    str->append(STRING_WITH_LEN(" AS "));
370
    append_identifier(thd, str, name, (uint) strlen(name));
unknown's avatar
unknown committed
371 372 373 374
  }
}


375 376 377
void Item::cleanup()
{
  DBUG_ENTER("Item::cleanup");
378
  DBUG_PRINT("info", ("Item: 0x%lx, Type: %d, name %s, original name %s",
379 380
		      this, (int)type(), name ? name : "(null)",
                      orig_name ? orig_name : "null"));
381
  fixed=0;
382
  marker= 0;
383 384
  if (orig_name)
    name= orig_name;
385 386 387
  DBUG_VOID_RETURN;
}

388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404

/*
  cleanup() item if it is 'fixed'

  SYNOPSIS
    cleanup_processor()
    arg - a dummy parameter, is not used here
*/

bool Item::cleanup_processor(byte *arg)
{
  if (fixed)
    cleanup();
  return FALSE;
}


405 406 407 408 409 410 411 412 413 414 415
/*
  rename item (used for views, cleanup() return original name)

  SYNOPSIS
    Item::rename()
    new_name	new name of item;
*/

void Item::rename(char *new_name)
{
  /*
unknown's avatar
unknown committed
416
    we can compare pointers to names here, because if name was not changed,
417 418 419 420 421 422 423 424
    pointer will be same
  */
  if (!orig_name && new_name != name)
    orig_name= name;
  name= new_name;
}


425 426 427 428 429 430 431
Item_ident::Item_ident(Name_resolution_context *context_arg,
                       const char *db_name_arg,const char *table_name_arg,
		       const char *field_name_arg)
  :orig_db_name(db_name_arg), orig_table_name(table_name_arg),
   orig_field_name(field_name_arg), context(context_arg),
   db_name(db_name_arg), table_name(table_name_arg),
   field_name(field_name_arg),
432
   alias_name_used(FALSE), cached_field_index(NO_CACHED_FIELD_INDEX),
433
   cached_table(0), depended_from(0)
unknown's avatar
unknown committed
434
{
435
  name = (char*) field_name_arg;
unknown's avatar
unknown committed
436 437
}

438

unknown's avatar
unknown committed
439
/* Constructor used by Item_field & Item_*_ref (see Item comment) */
440

441 442
Item_ident::Item_ident(THD *thd, Item_ident *item)
  :Item(thd, item),
443 444 445
   orig_db_name(item->orig_db_name),
   orig_table_name(item->orig_table_name), 
   orig_field_name(item->orig_field_name),
446
   context(item->context),
447 448 449
   db_name(item->db_name),
   table_name(item->table_name),
   field_name(item->field_name),
450
   alias_name_used(item->alias_name_used),
451
   cached_field_index(item->cached_field_index),
452
   cached_table(item->cached_table),
453
   depended_from(item->depended_from)
454
{}
455

456 457
void Item_ident::cleanup()
{
unknown's avatar
unknown committed
458
  DBUG_ENTER("Item_ident::cleanup");
unknown's avatar
unknown committed
459
#ifdef CANT_BE_USED_AS_MEMORY_IS_FREED
460 461 462 463 464 465
		       db_name ? db_name : "(null)",
                       orig_db_name ? orig_db_name : "(null)",
		       table_name ? table_name : "(null)",
                       orig_table_name ? orig_table_name : "(null)",
		       field_name ? field_name : "(null)",
                       orig_field_name ? orig_field_name : "(null)"));
unknown's avatar
unknown committed
466
#endif
467
  Item::cleanup();
468 469 470
  db_name= orig_db_name; 
  table_name= orig_table_name;
  field_name= orig_field_name;
471
  depended_from= 0;
unknown's avatar
unknown committed
472
  DBUG_VOID_RETURN;
473 474
}

unknown's avatar
unknown committed
475 476 477 478 479
bool Item_ident::remove_dependence_processor(byte * arg)
{
  DBUG_ENTER("Item_ident::remove_dependence_processor");
  if (depended_from == (st_select_lex *) arg)
    depended_from= 0;
480
  DBUG_RETURN(0);
unknown's avatar
unknown committed
481 482 483
}


484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501
/*
  Store the pointer to this item field into a list if not already there.

  SYNOPSIS
    Item_field::collect_item_field_processor()
    arg  pointer to a List<Item_field>

  DESCRIPTION
    The method is used by Item::walk to collect all unique Item_field objects
    from a tree of Items into a set of items represented as a list.

  IMPLEMENTATION
    Item_cond::walk() and Item_func::walk() stop the evaluation of the
    processor function for its arguments once the processor returns
    true.Therefore in order to force this method being called for all item
    arguments in a condition the method must return false.

  RETURN
502 503
    false to force the evaluation of collect_item_field_processor
          for the subsequent items.
504 505 506 507 508 509 510 511 512 513 514 515
*/

bool Item_field::collect_item_field_processor(byte *arg)
{
  DBUG_ENTER("Item_field::collect_item_field_processor");
  DBUG_PRINT("info", ("%s", field->field_name ? field->field_name : "noname"));
  List<Item_field> *item_list= (List<Item_field>*) arg;
  List_iterator<Item_field> item_list_it(*item_list);
  Item_field *curr_item;
  while ((curr_item= item_list_it++))
  {
    if (curr_item->eq(this, 1))
unknown's avatar
unknown committed
516
      DBUG_RETURN(FALSE); /* Already in the set. */
517 518
  }
  item_list->push_back(this);
unknown's avatar
unknown committed
519
  DBUG_RETURN(FALSE);
520 521 522
}


unknown's avatar
unknown committed
523 524 525 526
bool Item::check_cols(uint c)
{
  if (c != 1)
  {
unknown's avatar
unknown committed
527
    my_error(ER_OPERAND_COLUMNS, MYF(0), c);
unknown's avatar
unknown committed
528 529 530 531 532
    return 1;
  }
  return 0;
}

unknown's avatar
unknown committed
533 534

void Item::set_name(const char *str, uint length, CHARSET_INFO *cs)
unknown's avatar
unknown committed
535 536 537
{
  if (!length)
  {
unknown's avatar
unknown committed
538 539
    /* Empty string, used by AS or internal function like last_insert_id() */
    name= (char*) str;
540
    name_length= 0;
unknown's avatar
unknown committed
541 542
    return;
  }
543 544
  if (cs->ctype)
  {
unknown's avatar
unknown committed
545 546 547 548
    /*
      This will probably need a better implementation in the future:
      a function in CHARSET_INFO structure.
    */
549 550 551 552 553
    while (length && !my_isgraph(cs,*str))
    {						// Fix problem with yacc
      length--;
      str++;
    }
unknown's avatar
unknown committed
554
  }
unknown's avatar
unknown committed
555 556 557
  if (!my_charset_same(cs, system_charset_info))
  {
    uint32 res_length;
558
    name= sql_strmake_with_convert(str, name_length= length, cs,
unknown's avatar
unknown committed
559 560 561 562
				   MAX_ALIAS_NAME, system_charset_info,
				   &res_length);
  }
  else
563
    name= sql_strmake(str, (name_length= min(length,MAX_ALIAS_NAME)));
unknown's avatar
unknown committed
564 565
}

unknown's avatar
unknown committed
566

567
/*
568 569 570
  This function is called when:
  - Comparing items in the WHERE clause (when doing where optimization)
  - When trying to find an ORDER BY/GROUP BY item in the SELECT part
571 572 573
*/

bool Item::eq(const Item *item, bool binary_cmp) const
unknown's avatar
unknown committed
574
{
575 576 577 578 579
  /*
    Note, that this is never TRUE if item is a Item_param:
    for all basic constants we have special checks, and Item_param's
    type() can be only among basic constant types.
  */
unknown's avatar
unknown committed
580
  return type() == item->type() && name && item->name &&
581
    !my_strcasecmp(system_charset_info,name,item->name);
unknown's avatar
unknown committed
582 583
}

unknown's avatar
unknown committed
584

585 586
Item *Item::safe_charset_converter(CHARSET_INFO *tocs)
{
587 588
  Item_func_conv_charset *conv= new Item_func_conv_charset(this, tocs, 1);
  return conv->safe ? conv : NULL;
589 590 591
}


unknown's avatar
unknown committed
592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610
/*
  Created mostly for mysql_prepare_table(). Important
  when a string ENUM/SET column is described with a numeric default value:

  CREATE TABLE t1(a SET('a') DEFAULT 1);

  We cannot use generic Item::safe_charset_converter(), because
  the latter returns a non-fixed Item, so val_str() crashes afterwards.
  Override Item_num method, to return a fixed item.
*/
Item *Item_num::safe_charset_converter(CHARSET_INFO *tocs)
{
  Item_string *conv;
  char buf[64];
  String *s, tmp(buf, sizeof(buf), &my_charset_bin);
  s= val_str(&tmp);
  if ((conv= new Item_string(s->ptr(), s->length(), s->charset())))
  {
    conv->str_value.copy();
611
    conv->str_value.mark_as_const();
unknown's avatar
unknown committed
612 613 614 615 616
  }
  return conv;
}


617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648
Item *Item_static_int_func::safe_charset_converter(CHARSET_INFO *tocs)
{
  Item_string *conv;
  char buf[64];
  String *s, tmp(buf, sizeof(buf), &my_charset_bin);
  s= val_str(&tmp);
  if ((conv= new Item_static_string_func(func_name, s->ptr(), s->length(),
                                         s->charset())))
  {
    conv->str_value.copy();
    conv->str_value.mark_as_const();
  }
  return conv;
}


Item *Item_static_float_func::safe_charset_converter(CHARSET_INFO *tocs)
{
  Item_string *conv;
  char buf[64];
  String *s, tmp(buf, sizeof(buf), &my_charset_bin);
  s= val_str(&tmp);
  if ((conv= new Item_static_string_func(func_name, s->ptr(), s->length(),
                                         s->charset())))
  {
    conv->str_value.copy();
    conv->str_value.mark_as_const();
  }
  return conv;
}


649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667
Item *Item_string::safe_charset_converter(CHARSET_INFO *tocs)
{
  Item_string *conv;
  uint conv_errors;
  String tmp, cstr, *ostr= val_str(&tmp);
  cstr.copy(ostr->ptr(), ostr->length(), ostr->charset(), tocs, &conv_errors);
  if (conv_errors || !(conv= new Item_string(cstr.ptr(), cstr.length(),
                                             cstr.charset(),
                                             collation.derivation)))
  {
    /*
      Safe conversion is not possible (or EOM).
      We could not convert a string into the requested character set
      without data loss. The target charset does not cover all the
      characters from the string. Operation cannot be done correctly.
    */
    return NULL;
  }
  conv->str_value.copy();
unknown's avatar
unknown committed
668 669
  /* Ensure that no one is going to change the result string */
  conv->str_value.mark_as_const();
670 671 672 673
  return conv;
}


674 675 676 677 678
Item *Item_param::safe_charset_converter(CHARSET_INFO *tocs)
{
  if (const_item())
  {
    uint cnv_errors;
unknown's avatar
unknown committed
679 680 681 682 683 684 685 686
    String *ostr= val_str(&cnvstr);
    cnvitem->str_value.copy(ostr->ptr(), ostr->length(),
                            ostr->charset(), tocs, &cnv_errors);
    if (cnv_errors)
       return NULL;
    cnvitem->str_value.mark_as_const();
    cnvitem->max_length= cnvitem->str_value.numchars() * tocs->mbmaxlen;
    return cnvitem;
687 688 689 690 691
  }
  return NULL;
}


692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708
Item *Item_static_string_func::safe_charset_converter(CHARSET_INFO *tocs)
{
  Item_string *conv;
  uint conv_errors;
  String tmp, cstr, *ostr= val_str(&tmp);
  cstr.copy(ostr->ptr(), ostr->length(), ostr->charset(), tocs, &conv_errors);
  if (conv_errors ||
      !(conv= new Item_static_string_func(func_name,
                                          cstr.ptr(), cstr.length(),
                                          cstr.charset(),
                                          collation.derivation)))
  {
    /*
      Safe conversion is not possible (or EOM).
      We could not convert a string into the requested character set
      without data loss. The target charset does not cover all the
      characters from the string. Operation cannot be done correctly.
709 710 711 712
    */
    return NULL;
  }
  conv->str_value.copy();
unknown's avatar
unknown committed
713 714
  /* Ensure that no one is going to change the result string */
  conv->str_value.mark_as_const();
715 716 717 718
  return conv;
}


719 720
bool Item_string::eq(const Item *item, bool binary_cmp) const
{
721
  if (type() == item->type() && item->basic_const_item())
722 723
  {
    if (binary_cmp)
unknown's avatar
unknown committed
724
      return !stringcmp(&str_value, &item->str_value);
unknown's avatar
unknown committed
725 726
    return (collation.collation == item->collation.collation &&
	    !sortcmp(&str_value, &item->str_value, collation.collation));
727 728 729 730 731
  }
  return 0;
}


unknown's avatar
unknown committed
732 733 734 735 736
/*
  Get the value of the function as a TIME structure.
  As a extra convenience the time structure is reset on error!
 */

737
bool Item::get_date(TIME *ltime,uint fuzzydate)
unknown's avatar
unknown committed
738 739
{
  char buff[40];
unknown's avatar
unknown committed
740
  String tmp(buff,sizeof(buff), &my_charset_bin),*res;
unknown's avatar
unknown committed
741
  if (!(res=val_str(&tmp)) ||
742 743
      str_to_datetime_with_warn(res->ptr(), res->length(),
                                ltime, fuzzydate) <= MYSQL_TIMESTAMP_ERROR)
unknown's avatar
unknown committed
744 745 746 747 748 749 750 751 752 753 754 755 756 757 758
  {
    bzero((char*) ltime,sizeof(*ltime));
    return 1;
  }
  return 0;
}

/*
  Get time of first argument.
  As a extra convenience the time structure is reset on error!
 */

bool Item::get_time(TIME *ltime)
{
  char buff[40];
unknown's avatar
unknown committed
759
  String tmp(buff,sizeof(buff),&my_charset_bin),*res;
unknown's avatar
unknown committed
760
  if (!(res=val_str(&tmp)) ||
761
      str_to_time_with_warn(res->ptr(), res->length(), ltime))
unknown's avatar
unknown committed
762 763 764 765 766 767 768
  {
    bzero((char*) ltime,sizeof(*ltime));
    return 1;
  }
  return 0;
}

769
CHARSET_INFO *Item::default_charset()
770
{
unknown's avatar
unknown committed
771
  return current_thd->variables.collation_connection;
772 773
}

774

775 776 777 778 779 780 781 782 783 784 785 786
int Item::save_in_field_no_warnings(Field *field, bool no_conversions)
{
  int res;
  THD *thd= field->table->in_use;
  enum_check_fields tmp= thd->count_cuted_fields;
  thd->count_cuted_fields= CHECK_FIELD_IGNORE;
  res= save_in_field(field, no_conversions);
  thd->count_cuted_fields= tmp;
  return res;
}


787
/*****************************************************************************
788
  Item_sp_variable methods
789
*****************************************************************************/
790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822

Item_sp_variable::Item_sp_variable(char *sp_var_name_str,
                                   uint sp_var_name_length)
  :m_thd(0)
#ifndef DBUG_OFF
   , m_sp(0)
#endif
{
  m_name.str= sp_var_name_str;
  m_name.length= sp_var_name_length;
}


bool Item_sp_variable::fix_fields(THD *thd, Item **)
{
  Item *it;

  m_thd= thd; /* NOTE: this must be set before any this_xxx() */
  it= this_item();

  DBUG_ASSERT(it->fixed);

  max_length= it->max_length;
  decimals= it->decimals;
  unsigned_flag= it->unsigned_flag;
  fixed= 1;
  collation.set(it->collation.collation, it->collation.derivation);

  return FALSE;
}


double Item_sp_variable::val_real()
unknown's avatar
unknown committed
823 824 825 826
{
  DBUG_ASSERT(fixed);
  Item *it= this_item();
  double ret= it->val_real();
827
  null_value= it->null_value;
unknown's avatar
unknown committed
828 829 830 831
  return ret;
}


832
longlong Item_sp_variable::val_int()
unknown's avatar
unknown committed
833 834 835 836
{
  DBUG_ASSERT(fixed);
  Item *it= this_item();
  longlong ret= it->val_int();
837
  null_value= it->null_value;
unknown's avatar
unknown committed
838 839 840 841
  return ret;
}


842
String *Item_sp_variable::val_str(String *sp)
unknown's avatar
unknown committed
843 844 845
{
  DBUG_ASSERT(fixed);
  Item *it= this_item();
846
  String *res= it->val_str(sp);
847 848

  null_value= it->null_value;
849

850 851 852
  if (!res)
    return NULL;

853 854 855 856 857 858 859 860 861 862 863 864 865 866 867
  /*
    This way we mark returned value of val_str as const,
    so that various functions (e.g. CONCAT) won't try to
    modify the value of the Item. Analogous mechanism is
    implemented for Item_param.
    Without this trick Item_splocal could be changed as a
    side-effect of expression computation. Here is an example
    of what happens without it: suppose x is varchar local
    variable in a SP with initial value 'ab' Then
      select concat(x,'c');
    would change x's value to 'abc', as Item_func_concat::val_str()
    would use x's internal buffer to compute the result.
    This is intended behaviour of Item_func_concat. Comments to
    Item_param class contain some more details on the topic.
  */
868

869 870 871 872
  if (res != &str_value)
    str_value.set(res->ptr(), res->length(), res->charset());
  else
    res->mark_as_const();
873

874
  return &str_value;
unknown's avatar
unknown committed
875 876 877
}


878
my_decimal *Item_sp_variable::val_decimal(my_decimal *decimal_value)
unknown's avatar
unknown committed
879 880 881
{
  DBUG_ASSERT(fixed);
  Item *it= this_item();
882
  my_decimal *val= it->val_decimal(decimal_value);
883
  null_value= it->null_value;
unknown's avatar
unknown committed
884 885 886 887
  return val;
}


888
bool Item_sp_variable::is_null()
unknown's avatar
unknown committed
889
{
890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908
  return this_item()->is_null();
}


/*****************************************************************************
  Item_splocal methods
*****************************************************************************/

Item_splocal::Item_splocal(const LEX_STRING &sp_var_name,
                           uint sp_var_idx,
                           enum_field_types sp_var_type,
                           uint pos_in_q)
  :Item_sp_variable(sp_var_name.str, sp_var_name.length),
   m_var_idx(sp_var_idx), pos_in_query(pos_in_q)
{
  maybe_null= TRUE;

  m_type= sp_map_item_type(sp_var_type);
  m_result_type= sp_map_result_type(sp_var_type);
unknown's avatar
unknown committed
909 910 911
}


912 913 914
Item *
Item_splocal::this_item()
{
915 916 917 918 919 920 921 922 923 924 925
  DBUG_ASSERT(m_sp == m_thd->spcont->sp);

  return m_thd->spcont->get_item(m_var_idx);
}

const Item *
Item_splocal::this_item() const
{
  DBUG_ASSERT(m_sp == m_thd->spcont->sp);

  return m_thd->spcont->get_item(m_var_idx);
926 927
}

928 929

Item **
930
Item_splocal::this_item_addr(THD *thd, Item **)
931
{
932 933 934
  DBUG_ASSERT(m_sp == thd->spcont->sp);

  return thd->spcont->get_item_addr(m_var_idx);
935 936
}

937 938

void Item_splocal::print(String *str)
939
{
940 941 942 943
  str->reserve(m_name.length+8);
  str->append(m_name.str, m_name.length);
  str->append('@');
  str->qs_append(m_var_idx);
944 945
}

946 947 948 949 950 951

/*****************************************************************************
  Item_case_expr methods
*****************************************************************************/

Item_case_expr::Item_case_expr(int case_expr_id)
952
  :Item_sp_variable((char *) STRING_WITH_LEN("case_expr")),
953
   m_case_expr_id(case_expr_id)
954 955 956 957
{
}


958 959
Item *
Item_case_expr::this_item()
unknown's avatar
unknown committed
960
{
961 962 963
  DBUG_ASSERT(m_sp == m_thd->spcont->sp);

  return m_thd->spcont->get_case_expr(m_case_expr_id);
unknown's avatar
unknown committed
964 965 966
}


967 968 969

const Item *
Item_case_expr::this_item() const
unknown's avatar
unknown committed
970
{
971 972 973
  DBUG_ASSERT(m_sp == m_thd->spcont->sp);

  return m_thd->spcont->get_case_expr(m_case_expr_id);
unknown's avatar
unknown committed
974 975 976
}


977 978
Item **
Item_case_expr::this_item_addr(THD *thd, Item **)
unknown's avatar
unknown committed
979
{
980 981 982 983 984 985 986 987 988 989
  DBUG_ASSERT(m_sp == thd->spcont->sp);

  return thd->spcont->get_case_expr_addr(m_case_expr_id);
}


void Item_case_expr::print(String *str)
{
  str->append(STRING_WITH_LEN("case_expr@"));
  str->qs_append(m_case_expr_id);
unknown's avatar
unknown committed
990 991 992
}


993 994 995
/*****************************************************************************
  Item_name_const methods
*****************************************************************************/
996

997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027
double Item_name_const::val_real()
{
  DBUG_ASSERT(fixed);
  double ret= value_item->val_real();
  null_value= value_item->null_value;
  return ret;
}


longlong Item_name_const::val_int()
{
  DBUG_ASSERT(fixed);
  longlong ret= value_item->val_int();
  null_value= value_item->null_value;
  return ret;
}


String *Item_name_const::val_str(String *sp)
{
  DBUG_ASSERT(fixed);
  String *ret= value_item->val_str(sp);
  null_value= value_item->null_value;
  return ret;
}


my_decimal *Item_name_const::val_decimal(my_decimal *decimal_value)
{
  DBUG_ASSERT(fixed);
  my_decimal *val= value_item->val_decimal(decimal_value);
1028
  null_value= value_item->null_value;
1029 1030 1031 1032 1033 1034
  return val;
}


bool Item_name_const::is_null()
{
1035
  return value_item->is_null();
1036 1037 1038 1039 1040 1041 1042 1043
}

Item::Type Item_name_const::type() const
{
  return value_item->type();
}


1044
bool Item_name_const::fix_fields(THD *thd, Item **ref)
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069
{
  char buf[128];
  String *item_name;
  String s(buf, sizeof(buf), &my_charset_bin);
  s.length(0);

  if (value_item->fix_fields(thd, &value_item) ||
      name_item->fix_fields(thd, &name_item))
    return TRUE;
  if (!(value_item->const_item() && name_item->const_item()))
    return TRUE;

  if (!(item_name= name_item->val_str(&s)))
    return TRUE; /* Can't have a NULL name */

  set_name(item_name->ptr(), (uint) item_name->length(), system_charset_info);
  max_length= value_item->max_length;
  decimals= value_item->decimals;
  fixed= 1;
  return FALSE;
}


void Item_name_const::print(String *str)
{
1070
  str->append(STRING_WITH_LEN("NAME_CONST("));
1071 1072 1073 1074 1075 1076
  name_item->print(str);
  str->append(',');
  value_item->print(str);
  str->append(')');
}

1077

1078 1079 1080 1081 1082 1083 1084 1085 1086
/*
  Move SUM items out from item tree and replace with reference

  SYNOPSIS
    split_sum_func2()
    thd			Thread handler
    ref_pointer_array	Pointer to array of reference fields
    fields		All fields in select
    ref			Pointer to item
unknown's avatar
unknown committed
1087
    skip_registered     <=> function be must skipped for registered SUM items
1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099

  NOTES
   This is from split_sum_func2() for items that should be split

   All found SUM items are added FIRST in the fields list and
   we replace the item with a reference.

   thd->fatal_error() may be called if we are out of memory
*/


void Item::split_sum_func2(THD *thd, Item **ref_pointer_array,
unknown's avatar
unknown committed
1100 1101
                           List<Item> &fields, Item **ref, 
                           bool skip_registered)
1102
{
unknown's avatar
unknown committed
1103 1104 1105 1106
  /* An item of type Item_sum  is registered <=> ref_by != 0 */ 
  if (type() == SUM_FUNC_ITEM && skip_registered && 
      ((Item_sum *) this)->ref_by)
    return;                                                 
1107 1108 1109 1110 1111
  if (type() != SUM_FUNC_ITEM && with_sum_func)
  {
    /* Will split complicated items and ignore simple ones */
    split_sum_func(thd, ref_pointer_array, fields);
  }
1112 1113 1114
  else if ((type() == SUM_FUNC_ITEM || (used_tables() & ~PARAM_TABLE_BIT)) &&
           (type() != REF_ITEM ||
           ((Item_ref*)this)->ref_type() == Item_ref::VIEW_REF))
1115 1116 1117 1118 1119 1120 1121 1122
  {
    /*
      Replace item with a reference so that we can easily calculate
      it (in case of sum functions) or copy it (in case of fields)

      The test above is to ensure we don't do a reference for things
      that are constants (PARAM_TABLE_BIT is in effect a constant)
      or already referenced (for example an item in HAVING)
1123 1124
      Exception is Item_direct_view_ref which we need to convert to
      Item_ref to allow fields from view being stored in tmp table.
1125 1126
    */
    uint el= fields.elements;
unknown's avatar
unknown committed
1127
    Item *new_item, *real_itm= real_item();
1128

unknown's avatar
unknown committed
1129
    ref_pointer_array[el]= real_itm;
1130 1131
    if (!(new_item= new Item_ref(&thd->lex->current_select->context,
                                 ref_pointer_array + el, 0, name)))
1132
      return;                                   // fatal_error is set
unknown's avatar
unknown committed
1133
    fields.push_front(real_itm);
1134 1135 1136 1137 1138
    thd->change_item_tree(ref, new_item);
  }
}


1139 1140 1141 1142
/*
   Aggregate two collations together taking
   into account their coercibility (aka derivation):

unknown's avatar
unknown committed
1143
   0 == DERIVATION_EXPLICIT  - an explicitly written COLLATE clause
1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174
   1 == DERIVATION_NONE      - a mix of two different collations
   2 == DERIVATION_IMPLICIT  - a column
   3 == DERIVATION_COERCIBLE - a string constant

   The most important rules are:

   1. If collations are the same:
      chose this collation, and the strongest derivation.

   2. If collations are different:
     - Character sets may differ, but only if conversion without
       data loss is possible. The caller provides flags whether
       character set conversion attempts should be done. If no
       flags are substituted, then the character sets must be the same.
       Currently processed flags are:
         MY_COLL_ALLOW_SUPERSET_CONV  - allow conversion to a superset
         MY_COLL_ALLOW_COERCIBLE_CONV - allow conversion of a coercible value
     - two EXPLICIT collations produce an error, e.g. this is wrong:
       CONCAT(expr1 collate latin1_swedish_ci, expr2 collate latin1_german_ci)
     - the side with smaller derivation value wins,
       i.e. a column is stronger than a string constant,
       an explicit COLLATE clause is stronger than a column.
     - if derivations are the same, we have DERIVATION_NONE,
       we'll wait for an explicit COLLATE clause which possibly can
       come from another argument later: for example, this is valid,
       but we don't know yet when collecting the first two arguments:
         CONCAT(latin1_swedish_ci_column,
                latin1_german1_ci_column,
                expr COLLATE latin1_german2_ci)
*/
bool DTCollation::aggregate(DTCollation &dt, uint flags)
1175
{
1176
  if (!my_charset_same(collation, dt.collation))
1177
  {
1178 1179 1180
    /* 
       We do allow to use binary strings (like BLOBS)
       together with character strings.
unknown's avatar
unknown committed
1181
       Binaries have more precedence than a character
unknown's avatar
unknown committed
1182
       string of the same derivation.
1183
    */
1184
    if (collation == &my_charset_bin)
1185
    {
1186 1187 1188
      if (derivation <= dt.derivation)
	; // Do nothing
      else
1189 1190 1191
      {
	set(dt); 
      }
1192
    }
1193
    else if (dt.collation == &my_charset_bin)
1194
    {
1195
      if (dt.derivation <= derivation)
1196
      {
1197
        set(dt);
1198
      }
1199 1200
      else
       ; // Do nothing
1201
    }
1202
    else if ((flags & MY_COLL_ALLOW_SUPERSET_CONV) &&
unknown's avatar
unknown committed
1203
             collation->state & MY_CS_UNICODE &&
unknown's avatar
unknown committed
1204 1205 1206
             (derivation < dt.derivation ||
             (derivation == dt.derivation &&
             !(dt.collation->state & MY_CS_UNICODE))))
1207
    {
1208 1209 1210
      // Do nothing
    }
    else if ((flags & MY_COLL_ALLOW_SUPERSET_CONV) &&
unknown's avatar
unknown committed
1211
             dt.collation->state & MY_CS_UNICODE &&
unknown's avatar
unknown committed
1212 1213 1214
             (dt.derivation < derivation ||
              (dt.derivation == derivation &&
             !(collation->state & MY_CS_UNICODE))))
1215 1216 1217 1218 1219
    {
      set(dt);
    }
    else if ((flags & MY_COLL_ALLOW_COERCIBLE_CONV) &&
             derivation < dt.derivation &&
1220
             dt.derivation >= DERIVATION_SYSCONST)
1221 1222 1223 1224 1225
    {
      // Do nothing;
    }
    else if ((flags & MY_COLL_ALLOW_COERCIBLE_CONV) &&
             dt.derivation < derivation &&
1226
             derivation >= DERIVATION_SYSCONST)
1227 1228
    {
      set(dt);
1229
    }
1230 1231
    else
    {
1232
      // Cannot apply conversion
1233
      set(0, DERIVATION_NONE);
1234
      return 1;
1235
    }
1236
  }
1237
  else if (derivation < dt.derivation)
1238
  {
1239
    // Do nothing
1240
  }
1241
  else if (dt.derivation < derivation)
1242
  {
1243
    set(dt);
1244
  }
1245 1246 1247
  else
  { 
    if (collation == dt.collation)
1248
    {
1249 1250 1251 1252 1253
      // Do nothing
    }
    else 
    {
      if (derivation == DERIVATION_EXPLICIT)
1254
      {
1255 1256
	set(0, DERIVATION_NONE);
	return 1;
1257
      }
1258 1259
      if (collation->state & MY_CS_BINSORT)
        return 0;
unknown's avatar
unknown committed
1260
      if (dt.collation->state & MY_CS_BINSORT)
1261 1262 1263 1264
      {
        set(dt);
        return 0;
      }
1265
      CHARSET_INFO *bin= get_charset_by_csname(collation->csname, 
1266
                                               MY_CS_BINSORT,MYF(0));
1267
      set(bin, DERIVATION_NONE);
1268
    }
1269 1270 1271 1272
  }
  return 0;
}

1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381
/******************************/
static
void my_coll_agg_error(DTCollation &c1, DTCollation &c2, const char *fname)
{
  my_error(ER_CANT_AGGREGATE_2COLLATIONS,MYF(0),
           c1.collation->name,c1.derivation_name(),
           c2.collation->name,c2.derivation_name(),
           fname);
}


static
void my_coll_agg_error(DTCollation &c1, DTCollation &c2, DTCollation &c3,
                       const char *fname)
{
  my_error(ER_CANT_AGGREGATE_3COLLATIONS,MYF(0),
  	   c1.collation->name,c1.derivation_name(),
	   c2.collation->name,c2.derivation_name(),
	   c3.collation->name,c3.derivation_name(),
	   fname);
}


static
void my_coll_agg_error(Item** args, uint count, const char *fname)
{
  if (count == 2)
    my_coll_agg_error(args[0]->collation, args[1]->collation, fname);
  else if (count == 3)
    my_coll_agg_error(args[0]->collation, args[1]->collation,
                      args[2]->collation, fname);
  else
    my_error(ER_CANT_AGGREGATE_NCOLLATIONS,MYF(0),fname);
}


bool agg_item_collations(DTCollation &c, const char *fname,
                         Item **av, uint count, uint flags)
{
  uint i;
  c.set(av[0]->collation);
  for (i= 1; i < count; i++)
  {
    if (c.aggregate(av[i]->collation, flags))
    {
      my_coll_agg_error(av, count, fname);
      return TRUE;
    }
  }
  if ((flags & MY_COLL_DISALLOW_NONE) &&
      c.derivation == DERIVATION_NONE)
  {
    my_coll_agg_error(av, count, fname);
    return TRUE;
  }
  return FALSE;
}


bool agg_item_collations_for_comparison(DTCollation &c, const char *fname,
                                        Item **av, uint count, uint flags)
{
  return (agg_item_collations(c, fname, av, count,
                              flags | MY_COLL_DISALLOW_NONE));
}


/* 
  Collect arguments' character sets together.
  We allow to apply automatic character set conversion in some cases.
  The conditions when conversion is possible are:
  - arguments A and B have different charsets
  - A wins according to coercibility rules
    (i.e. a column is stronger than a string constant,
     an explicit COLLATE clause is stronger than a column)
  - character set of A is either superset for character set of B,
    or B is a string constant which can be converted into the
    character set of A without data loss.
    
  If all of the above is true, then it's possible to convert
  B into the character set of A, and then compare according
  to the collation of A.
  
  For functions with more than two arguments:

    collect(A,B,C) ::= collect(collect(A,B),C)
*/

bool agg_item_charsets(DTCollation &coll, const char *fname,
                       Item **args, uint nargs, uint flags)
{
  Item **arg, **last, *safe_args[2];
  if (agg_item_collations(coll, fname, args, nargs, flags))
    return TRUE;

  /*
    For better error reporting: save the first and the second argument.
    We need this only if the the number of args is 3 or 2:
    - for a longer argument list, "Illegal mix of collations"
      doesn't display each argument's characteristics.
    - if nargs is 1, then this error cannot happen.
  */
  if (nargs >=2 && nargs <= 3)
  {
    safe_args[0]= args[0];
    safe_args[1]= args[1];
  }

  THD *thd= current_thd;
1382
  Query_arena *arena, backup;
1383 1384 1385 1386 1387
  bool res= FALSE;
  /*
    In case we're in statement prepare, create conversion item
    in its memory: it will be reused on each execute.
  */
unknown's avatar
unknown committed
1388
  arena= thd->activate_stmt_arena_if_needed(&backup);
1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410

  for (arg= args, last= args + nargs; arg < last; arg++)
  {
    Item* conv;
    uint32 dummy_offset;
    if (!String::needs_conversion(0, coll.collation,
                                  (*arg)->collation.collation,
                                  &dummy_offset))
      continue;

    if (!(conv= (*arg)->safe_charset_converter(coll.collation)))
    {
      if (nargs >=2 && nargs <= 3)
      {
        /* restore the original arguments for better error message */
        args[0]= safe_args[0];
        args[1]= safe_args[1];
      }
      my_coll_agg_error(args, nargs, fname);
      res= TRUE;
      break; // we cannot return here, we need to restore "arena".
    }
1411 1412
    if ((*arg)->type() == Item::FIELD_ITEM)
      ((Item_field *)(*arg))->no_const_subst= 1;
1413 1414 1415 1416 1417 1418 1419 1420 1421 1422
    /*
      If in statement prepare, then we create a converter for two
      constant items, do it once and then reuse it.
      If we're in execution of a prepared statement, arena is NULL,
      and the conv was created in runtime memory. This can be
      the case only if the argument is a parameter marker ('?'),
      because for all true constants the charset converter has already
      been created in prepare. In this case register the change for
      rollback.
    */
1423
    if (arena && arena->is_conventional())
1424 1425 1426
      *arg= conv;
    else
      thd->change_item_tree(arg, conv);
1427 1428 1429 1430 1431
    /*
      We do not check conv->fixed, because Item_func_conv_charset which can
      be return by safe_charset_converter can't be fixed at creation
    */
    conv->fix_fields(thd, arg);
1432 1433
  }
  if (arena)
unknown's avatar
unknown committed
1434
    thd->restore_active_arena(arena, &backup);
1435 1436 1437 1438 1439 1440 1441 1442
  return res;
}




/**********************************************/

unknown's avatar
unknown committed
1443
Item_field::Item_field(Field *f)
1444
  :Item_ident(0, NullS, *f->table_name, f->field_name),
unknown's avatar
unknown committed
1445
  item_equal(0), no_const_subst(0),
unknown's avatar
VIEW  
unknown committed
1446
   have_privileges(0), any_privileges(0)
unknown's avatar
unknown committed
1447 1448
{
  set_field(f);
1449 1450 1451 1452 1453
  /*
    field_name and talbe_name should not point to garbage
    if this item is to be reused
  */
  orig_table_name= orig_field_name= "";
unknown's avatar
unknown committed
1454 1455
}

1456 1457 1458
Item_field::Item_field(THD *thd, Name_resolution_context *context_arg,
                       Field *f)
  :Item_ident(context_arg, f->table->s->db, *f->table_name, f->field_name),
unknown's avatar
unknown committed
1459
   item_equal(0), no_const_subst(0),
unknown's avatar
VIEW  
unknown committed
1460
   have_privileges(0), any_privileges(0)
unknown's avatar
unknown committed
1461
{
1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476
  /*
    We always need to provide Item_field with a fully qualified field
    name to avoid ambiguity when executing prepared statements like
    SELECT * from d1.t1, d2.t1; (assuming d1.t1 and d2.t1 have columns
    with same names).
    This is because prepared statements never deal with wildcards in
    select list ('*') and always fix fields using fully specified path
    (i.e. db.table.column).
    No check for OOM: if db_name is NULL, we'll just get
    "Field not found" error.
    We need to copy db_name, table_name and field_name because they must
    be allocated in the statement memory, not in table memory (the table
    structure can go away and pop up again between subsequent executions
    of a prepared statement).
  */
unknown's avatar
unknown committed
1477
  if (thd->stmt_arena->is_stmt_prepare_or_first_sp_execute())
1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489
  {
    if (db_name)
      orig_db_name= thd->strdup(db_name);
    orig_table_name= thd->strdup(table_name);
    orig_field_name= thd->strdup(field_name);
    /*
      We don't restore 'name' in cleanup because it's not changed
      during execution. Still we need it to point to persistent
      memory if this item is to be reused.
    */
    name= (char*) orig_field_name;
  }
unknown's avatar
unknown committed
1490 1491 1492
  set_field(f);
}

1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503

Item_field::Item_field(Name_resolution_context *context_arg,
                       const char *db_arg,const char *table_name_arg,
                       const char *field_name_arg)
  :Item_ident(context_arg, db_arg,table_name_arg,field_name_arg),
   field(0), result_field(0), item_equal(0), no_const_subst(0),
   have_privileges(0), any_privileges(0)
{
  collation.set(DERIVATION_IMPLICIT);
}

1504
// Constructor need to process subselect with temporary tables (see Item)
1505
Item_field::Item_field(THD *thd, Item_field *item)
1506
  :Item_ident(thd, item),
1507
   field(item->field),
unknown's avatar
VIEW  
unknown committed
1508
   result_field(item->result_field),
unknown's avatar
unknown committed
1509 1510
   item_equal(item->item_equal),
   no_const_subst(item->no_const_subst),
unknown's avatar
VIEW  
unknown committed
1511 1512
   have_privileges(item->have_privileges),
   any_privileges(item->any_privileges)
1513 1514 1515
{
  collation.set(DERIVATION_IMPLICIT);
}
unknown's avatar
unknown committed
1516 1517 1518 1519 1520 1521

void Item_field::set_field(Field *field_par)
{
  field=result_field=field_par;			// for easy coding with fields
  maybe_null=field->maybe_null();
  decimals= field->decimals();
unknown's avatar
Merge  
unknown committed
1522
  max_length= field_par->max_length();
1523 1524 1525
  table_name= *field_par->table_name;
  field_name= field_par->field_name;
  db_name= field_par->table->s->db;
unknown's avatar
unknown committed
1526
  alias_name_used= field_par->table->alias_name_used;
1527
  unsigned_flag=test(field_par->flags & UNSIGNED_FLAG);
1528
  collation.set(field_par->charset(), DERIVATION_IMPLICIT);
1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543
  fixed= 1;
}


/*
  Reset this item to point to a field from the new temporary table.
  This is used when we create a new temporary table for each execution
  of prepared statement.
*/

void Item_field::reset_field(Field *f)
{
  set_field(f);
  /* 'name' is pointing at field->field_name of old field */
  name= (char*) f->field_name;
unknown's avatar
unknown committed
1544 1545 1546 1547 1548
}

const char *Item_ident::full_name() const
{
  char *tmp;
1549
  if (!table_name || !field_name)
unknown's avatar
unknown committed
1550
    return field_name ? field_name : name ? name : "tmp_field";
unknown's avatar
unknown committed
1551
  if (db_name && db_name[0])
unknown's avatar
unknown committed
1552
  {
unknown's avatar
unknown committed
1553 1554
    tmp=(char*) sql_alloc((uint) strlen(db_name)+(uint) strlen(table_name)+
			  (uint) strlen(field_name)+3);
unknown's avatar
unknown committed
1555 1556 1557 1558
    strxmov(tmp,db_name,".",table_name,".",field_name,NullS);
  }
  else
  {
1559 1560 1561 1562 1563 1564 1565 1566
    if (table_name[0])
    {
      tmp= (char*) sql_alloc((uint) strlen(table_name) +
			     (uint) strlen(field_name) + 2);
      strxmov(tmp, table_name, ".", field_name, NullS);
    }
    else
      tmp= (char*) field_name;
unknown's avatar
unknown committed
1567 1568 1569 1570
  }
  return tmp;
}

1571 1572
void Item_ident::print(String *str)
{
1573
  THD *thd= current_thd;
1574 1575
  char d_name_buff[MAX_ALIAS_NAME], t_name_buff[MAX_ALIAS_NAME];
  const char *d_name= db_name, *t_name= table_name;
unknown's avatar
unknown committed
1576 1577
  if (lower_case_table_names== 1 ||
      (lower_case_table_names == 2 && !alias_name_used))
1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592
  {
    if (table_name && table_name[0])
    {
      strmov(t_name_buff, table_name);
      my_casedn_str(files_charset_info, t_name_buff);
      t_name= t_name_buff;
    }
    if (db_name && db_name[0])
    {
      strmov(d_name_buff, db_name);
      my_casedn_str(files_charset_info, d_name_buff);
      d_name= d_name_buff;
    }
  }

1593 1594
  if (!table_name || !field_name)
  {
1595
    const char *nm= field_name ? field_name : name ? name : "tmp_field";
1596
    append_identifier(thd, str, nm, (uint) strlen(nm));
1597 1598
    return;
  }
unknown's avatar
unknown committed
1599
  if (db_name && db_name[0] && !alias_name_used)
1600
  {
1601 1602 1603
    if (!(cached_table && cached_table->belong_to_view &&
          cached_table->belong_to_view->compact_view_format))
    {
1604
      append_identifier(thd, str, d_name, (uint)strlen(d_name));
1605 1606
      str->append('.');
    }
1607
    append_identifier(thd, str, t_name, (uint)strlen(t_name));
1608
    str->append('.');
1609
    append_identifier(thd, str, field_name, (uint)strlen(field_name));
1610 1611 1612 1613 1614
  }
  else
  {
    if (table_name[0])
    {
1615
      append_identifier(thd, str, t_name, (uint) strlen(t_name));
1616
      str->append('.');
1617
      append_identifier(thd, str, field_name, (uint) strlen(field_name));
1618 1619
    }
    else
1620
      append_identifier(thd, str, field_name, (uint) strlen(field_name));
1621 1622 1623
  }
}

unknown's avatar
unknown committed
1624 1625 1626
/* ARGSUSED */
String *Item_field::val_str(String *str)
{
1627
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1628 1629
  if ((null_value=field->is_null()))
    return 0;
1630
  str->set_charset(str_value.charset());
unknown's avatar
unknown committed
1631 1632 1633
  return field->val_str(str,&str_value);
}

unknown's avatar
unknown committed
1634

1635
double Item_field::val_real()
unknown's avatar
unknown committed
1636
{
1637
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1638 1639 1640 1641 1642
  if ((null_value=field->is_null()))
    return 0.0;
  return field->val_real();
}

unknown's avatar
unknown committed
1643

unknown's avatar
unknown committed
1644 1645
longlong Item_field::val_int()
{
1646
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1647 1648 1649 1650 1651 1652
  if ((null_value=field->is_null()))
    return 0;
  return field->val_int();
}


unknown's avatar
unknown committed
1653 1654 1655 1656 1657 1658 1659 1660
my_decimal *Item_field::val_decimal(my_decimal *decimal_value)
{
  if ((null_value= field->is_null()))
    return 0;
  return field->val_decimal(decimal_value);
}


unknown's avatar
unknown committed
1661 1662 1663 1664
String *Item_field::str_result(String *str)
{
  if ((null_value=result_field->is_null()))
    return 0;
1665
  str->set_charset(str_value.charset());
unknown's avatar
unknown committed
1666 1667 1668
  return result_field->val_str(str,&str_value);
}

1669
bool Item_field::get_date(TIME *ltime,uint fuzzydate)
unknown's avatar
unknown committed
1670 1671 1672 1673 1674 1675 1676 1677 1678
{
  if ((null_value=field->is_null()) || field->get_date(ltime,fuzzydate))
  {
    bzero((char*) ltime,sizeof(*ltime));
    return 1;
  }
  return 0;
}

1679
bool Item_field::get_date_result(TIME *ltime,uint fuzzydate)
1680 1681 1682 1683 1684 1685 1686 1687 1688 1689
{
  if ((null_value=result_field->is_null()) ||
      result_field->get_date(ltime,fuzzydate))
  {
    bzero((char*) ltime,sizeof(*ltime));
    return 1;
  }
  return 0;
}

unknown's avatar
unknown committed
1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713
bool Item_field::get_time(TIME *ltime)
{
  if ((null_value=field->is_null()) || field->get_time(ltime))
  {
    bzero((char*) ltime,sizeof(*ltime));
    return 1;
  }
  return 0;
}

double Item_field::val_result()
{
  if ((null_value=result_field->is_null()))
    return 0.0;
  return result_field->val_real();
}

longlong Item_field::val_int_result()
{
  if ((null_value=result_field->is_null()))
    return 0;
  return result_field->val_int();
}

1714

unknown's avatar
unknown committed
1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726
my_decimal *Item_field::val_decimal_result(my_decimal *decimal_value)
{
  if ((null_value= result_field->is_null()))
    return 0;
  return result_field->val_decimal(decimal_value);
}


bool Item_field::val_bool_result()
{
  if ((null_value= result_field->is_null()))
    return FALSE;
1727
  switch (result_field->result_type()) {
unknown's avatar
unknown committed
1728
  case INT_RESULT:
1729
    return result_field->val_int() != 0;
unknown's avatar
unknown committed
1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743
  case DECIMAL_RESULT:
  {
    my_decimal decimal_value;
    my_decimal *val= result_field->val_decimal(&decimal_value);
    if (val)
      return !my_decimal_is_zero(val);
    return 0;
  }
  case REAL_RESULT:
  case STRING_RESULT:
    return result_field->val_real() != 0.0;
  case ROW_RESULT:
  default:
    DBUG_ASSERT(0);
1744
    return 0;                                   // Shut up compiler
unknown's avatar
unknown committed
1745 1746 1747 1748
  }
}


1749
bool Item_field::eq(const Item *item, bool binary_cmp) const
unknown's avatar
unknown committed
1750
{
1751 1752 1753 1754
  if (item->type() != FIELD_ITEM)
    return 0;
  
  Item_field *item_field= (Item_field*) item;
unknown's avatar
unknown committed
1755
  if (item_field->field && field)
1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768
    return item_field->field == field;
  /*
    We may come here when we are trying to find a function in a GROUP BY
    clause from the select list.
    In this case the '100 % correct' way to do this would be to first
    run fix_fields() on the GROUP BY item and then retry this function, but
    I think it's better to relax the checking a bit as we will in
    most cases do the correct thing by just checking the field name.
    (In cases where we would choose wrong we would have to generate a
    ER_NON_UNIQ_ERROR).
  */
  return (!my_strcasecmp(system_charset_info, item_field->name,
			 field_name) &&
unknown's avatar
unknown committed
1769
	  (!item_field->table_name || !table_name ||
1770 1771
	   (!my_strcasecmp(table_alias_charset, item_field->table_name,
			   table_name) &&
unknown's avatar
unknown committed
1772
	    (!item_field->db_name || !db_name ||
1773 1774
	     (item_field->db_name && !strcmp(item_field->db_name,
					     db_name))))));
unknown's avatar
unknown committed
1775 1776
}

1777

unknown's avatar
unknown committed
1778 1779 1780 1781
table_map Item_field::used_tables() const
{
  if (field->table->const_table)
    return 0;					// const item
unknown's avatar
unknown committed
1782
  return (depended_from ? OUTER_REF_TABLE_BIT : field->table->map);
unknown's avatar
unknown committed
1783 1784
}

1785

1786
Item *Item_field::get_tmp_table_item(THD *thd)
1787
{
1788
  Item_field *new_item= new Item_field(thd, this);
1789 1790 1791 1792
  if (new_item)
    new_item->field= new_item->result_field;
  return new_item;
}
unknown's avatar
unknown committed
1793

1794

unknown's avatar
unknown committed
1795
/*
1796 1797 1798
  Create an item from a string we KNOW points to a valid longlong
  end \0 terminated number string.
  This is always 'signed'. Unsigned values are created with Item_uint()
unknown's avatar
unknown committed
1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811
*/

Item_int::Item_int(const char *str_arg, uint length)
{
  char *end_ptr= (char*) str_arg + length;
  int error;
  value= my_strtoll10(str_arg, &end_ptr, &error);
  max_length= (uint) (end_ptr - str_arg);
  name= (char*) str_arg;
  fixed= 1;
}


unknown's avatar
unknown committed
1812 1813 1814 1815 1816 1817
my_decimal *Item_int::val_decimal(my_decimal *decimal_value)
{
  int2my_decimal(E_DEC_FATAL_ERROR, value, unsigned_flag, decimal_value);
  return decimal_value;
}

unknown's avatar
unknown committed
1818 1819
String *Item_int::val_str(String *str)
{
unknown's avatar
unknown committed
1820
  // following assert is redundant, because fixed=1 assigned in constructor
1821
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1822
  str->set(value, &my_charset_bin);
unknown's avatar
unknown committed
1823 1824 1825 1826 1827
  return str;
}

void Item_int::print(String *str)
{
unknown's avatar
unknown committed
1828 1829
  // my_charset_bin is good enough for numbers
  str_value.set(value, &my_charset_bin);
unknown's avatar
unknown committed
1830
  str->append(str_value);
unknown's avatar
unknown committed
1831 1832
}

1833

unknown's avatar
unknown committed
1834 1835 1836 1837 1838 1839 1840
Item_uint::Item_uint(const char *str_arg, uint length):
  Item_int(str_arg, length)
{
  unsigned_flag= 1;
}


1841 1842 1843 1844 1845 1846 1847
Item_uint::Item_uint(const char *str_arg, longlong i, uint length):
  Item_int(str_arg, i, length)
{
  unsigned_flag= 1;
}


unknown's avatar
unknown committed
1848 1849
String *Item_uint::val_str(String *str)
{
unknown's avatar
unknown committed
1850
  // following assert is redundant, because fixed=1 assigned in constructor
1851
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1852
  str->set((ulonglong) value, &my_charset_bin);
unknown's avatar
unknown committed
1853 1854 1855
  return str;
}

1856

unknown's avatar
unknown committed
1857 1858
void Item_uint::print(String *str)
{
1859
  // latin1 is good enough for numbers
unknown's avatar
unknown committed
1860 1861
  str_value.set((ulonglong) value, default_charset());
  str->append(str_value);
unknown's avatar
unknown committed
1862 1863
}

unknown's avatar
unknown committed
1864

unknown's avatar
unknown committed
1865 1866 1867 1868 1869 1870 1871
Item_decimal::Item_decimal(const char *str_arg, uint length,
                           CHARSET_INFO *charset)
{
  str2my_decimal(E_DEC_FATAL_ERROR, str_arg, length, charset, &decimal_value);
  name= (char*) str_arg;
  decimals= (uint8) decimal_value.frac;
  fixed= 1;
1872
  unsigned_flag= !decimal_value.sign();
unknown's avatar
unknown committed
1873 1874
  max_length= my_decimal_precision_to_length(decimal_value.intg + decimals,
                                             decimals, unsigned_flag);
unknown's avatar
unknown committed
1875 1876 1877 1878 1879 1880 1881
}

Item_decimal::Item_decimal(longlong val, bool unsig)
{
  int2my_decimal(E_DEC_FATAL_ERROR, val, unsig, &decimal_value);
  decimals= (uint8) decimal_value.frac;
  fixed= 1;
1882
  unsigned_flag= !decimal_value.sign();
unknown's avatar
unknown committed
1883 1884
  max_length= my_decimal_precision_to_length(decimal_value.intg + decimals,
                                             decimals, unsigned_flag);
unknown's avatar
unknown committed
1885 1886 1887 1888 1889 1890 1891 1892
}


Item_decimal::Item_decimal(double val, int precision, int scale)
{
  double2my_decimal(E_DEC_FATAL_ERROR, val, &decimal_value);
  decimals= (uint8) decimal_value.frac;
  fixed= 1;
1893
  unsigned_flag= !decimal_value.sign();
unknown's avatar
unknown committed
1894 1895
  max_length= my_decimal_precision_to_length(decimal_value.intg + decimals,
                                             decimals, unsigned_flag);
unknown's avatar
unknown committed
1896 1897 1898 1899 1900 1901 1902 1903 1904 1905
}


Item_decimal::Item_decimal(const char *str, const my_decimal *val_arg,
                           uint decimal_par, uint length)
{
  my_decimal2decimal(val_arg, &decimal_value);
  name= (char*) str;
  decimals= (uint8) decimal_par;
  max_length= length;
1906
  unsigned_flag= !decimal_value.sign();
unknown's avatar
unknown committed
1907 1908 1909 1910 1911 1912 1913 1914 1915
  fixed= 1;
}


Item_decimal::Item_decimal(my_decimal *value_par)
{
  my_decimal2decimal(value_par, &decimal_value);
  decimals= (uint8) decimal_value.frac;
  fixed= 1;
1916
  unsigned_flag= !decimal_value.sign();
unknown's avatar
unknown committed
1917
  max_length= my_decimal_precision_to_length(decimal_value.intg + decimals,
1918
                                             decimals, unsigned_flag);
unknown's avatar
unknown committed
1919 1920 1921 1922 1923
}


Item_decimal::Item_decimal(const char *bin, int precision, int scale)
{
unknown's avatar
unknown committed
1924 1925
  binary2my_decimal(E_DEC_FATAL_ERROR, bin,
                    &decimal_value, precision, scale);
unknown's avatar
unknown committed
1926 1927
  decimals= (uint8) decimal_value.frac;
  fixed= 1;
1928
  unsigned_flag= !decimal_value.sign();
unknown's avatar
unknown committed
1929
  max_length= my_decimal_precision_to_length(precision, decimals,
1930
                                             unsigned_flag);
unknown's avatar
unknown committed
1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961
}


longlong Item_decimal::val_int()
{
  longlong result;
  my_decimal2int(E_DEC_FATAL_ERROR, &decimal_value, unsigned_flag, &result);
  return result;
}

double Item_decimal::val_real()
{
  double result;
  my_decimal2double(E_DEC_FATAL_ERROR, &decimal_value, &result);
  return result;
}

String *Item_decimal::val_str(String *result)
{
  result->set_charset(&my_charset_bin);
  my_decimal2string(E_DEC_FATAL_ERROR, &decimal_value, 0, 0, 0, result);
  return result;
}

void Item_decimal::print(String *str)
{
  my_decimal2string(E_DEC_FATAL_ERROR, &decimal_value, 0, 0, 0, &str_value);
  str->append(str_value);
}


1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979
bool Item_decimal::eq(const Item *item, bool binary_cmp) const
{
  if (type() == item->type() && item->basic_const_item())
  {
    /*
      We need to cast off const to call val_decimal(). This should
      be OK for a basic constant. Additionally, we can pass 0 as
      a true decimal constant will return its internal decimal
      storage and ignore the argument.
    */
    Item *arg= (Item*) item;
    my_decimal *value= arg->val_decimal(0);
    return !my_decimal_cmp(&decimal_value, value);
  }
  return 0;
}


unknown's avatar
unknown committed
1980
String *Item_float::val_str(String *str)
unknown's avatar
unknown committed
1981
{
unknown's avatar
unknown committed
1982
  // following assert is redundant, because fixed=1 assigned in constructor
1983
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1984
  str->set(value,decimals,&my_charset_bin);
unknown's avatar
unknown committed
1985 1986 1987
  return str;
}

1988

unknown's avatar
unknown committed
1989 1990 1991 1992 1993 1994 1995 1996 1997
my_decimal *Item_float::val_decimal(my_decimal *decimal_value)
{
  // following assert is redundant, because fixed=1 assigned in constructor
  DBUG_ASSERT(fixed == 1);
  double2my_decimal(E_DEC_FATAL_ERROR, value, decimal_value);
  return (decimal_value);
}


unknown's avatar
unknown committed
1998 1999
void Item_string::print(String *str)
{
2000 2001
  str->append('_');
  str->append(collation.collation->csname);
unknown's avatar
unknown committed
2002
  str->append('\'');
unknown's avatar
unknown committed
2003
  str_value.print(str);
unknown's avatar
unknown committed
2004 2005 2006
  str->append('\'');
}

unknown's avatar
unknown committed
2007

2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026
inline bool check_if_only_end_space(CHARSET_INFO *cs, char *str, char *end)
{
  return str+ cs->cset->scan(cs, str, end, MY_SEQ_SPACES) == end;
}


double Item_string::val_real()
{
  DBUG_ASSERT(fixed == 1);
  int error;
  char *end, *org_end;
  double tmp;
  CHARSET_INFO *cs= str_value.charset();

  org_end= (char*) str_value.ptr() + str_value.length();
  tmp= my_strntod(cs, (char*) str_value.ptr(), str_value.length(), &end,
                  &error);
  if (error || (end != org_end && !check_if_only_end_space(cs, end, org_end)))
  {
2027 2028 2029 2030
    /*
      We can use str_value.ptr() here as Item_string is gurantee to put an
      end \0 here.
    */
2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048
    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
                        ER_TRUNCATED_WRONG_VALUE,
                        ER(ER_TRUNCATED_WRONG_VALUE), "DOUBLE",
                        str_value.ptr());
  }
  return tmp;
}


longlong Item_string::val_int()
{
  DBUG_ASSERT(fixed == 1);
  int err;
  longlong tmp;
  char *end= (char*) str_value.ptr()+ str_value.length();
  char *org_end= end;
  CHARSET_INFO *cs= str_value.charset();

unknown's avatar
unknown committed
2049
  tmp= (*(cs->cset->strtoll10))(cs, str_value.ptr(), &end, &err);
2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065
  /*
    TODO: Give error if we wanted a signed integer and we got an unsigned
    one
  */
  if (err > 0 ||
      (end != org_end && !check_if_only_end_space(cs, end, org_end)))
  {
    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
                        ER_TRUNCATED_WRONG_VALUE,
                        ER(ER_TRUNCATED_WRONG_VALUE), "INTEGER",
                        str_value.ptr());
  }
  return tmp;
}


unknown's avatar
unknown committed
2066 2067
my_decimal *Item_string::val_decimal(my_decimal *decimal_value)
{
2068
  return val_decimal_from_string(decimal_value);
unknown's avatar
unknown committed
2069 2070 2071
}


2072 2073
bool Item_null::eq(const Item *item, bool binary_cmp) const
{ return item->type() == type(); }
unknown's avatar
unknown committed
2074 2075


2076
double Item_null::val_real()
2077
{
unknown's avatar
unknown committed
2078 2079
  // following assert is redundant, because fixed=1 assigned in constructor
  DBUG_ASSERT(fixed == 1);
2080 2081 2082 2083 2084
  null_value=1;
  return 0.0;
}
longlong Item_null::val_int()
{
unknown's avatar
unknown committed
2085 2086
  // following assert is redundant, because fixed=1 assigned in constructor
  DBUG_ASSERT(fixed == 1);
2087 2088 2089
  null_value=1;
  return 0;
}
unknown's avatar
unknown committed
2090 2091
/* ARGSUSED */
String *Item_null::val_str(String *str)
2092
{
unknown's avatar
unknown committed
2093 2094
  // following assert is redundant, because fixed=1 assigned in constructor
  DBUG_ASSERT(fixed == 1);
2095 2096 2097
  null_value=1;
  return 0;
}
unknown's avatar
unknown committed
2098

unknown's avatar
unknown committed
2099 2100 2101 2102 2103
my_decimal *Item_null::val_decimal(my_decimal *decimal_value)
{
  return 0;
}

unknown's avatar
unknown committed
2104

2105 2106 2107 2108 2109 2110
Item *Item_null::safe_charset_converter(CHARSET_INFO *tocs)
{
  collation.set(tocs);
  return this;
}

2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125
/*********************** Item_param related ******************************/

/* 
  Default function of Item_param::set_param_func, so in case
  of malformed packet the server won't SIGSEGV
*/

static void
default_set_param_func(Item_param *param,
                       uchar **pos __attribute__((unused)),
                       ulong len __attribute__((unused)))
{
  param->set_null();
}

2126

2127 2128
Item_param::Item_param(unsigned pos_in_query_arg) :
  state(NO_VALUE),
2129
  item_result_type(STRING_RESULT),
2130 2131
  /* Don't pretend to be a literal unless value for this item is set. */
  item_type(PARAM_ITEM),
2132
  param_type(MYSQL_TYPE_VARCHAR),
2133
  pos_in_query(pos_in_query_arg),
2134 2135 2136
  set_param_func(default_set_param_func)
{
  name= (char*) "?";
2137 2138 2139 2140 2141 2142
  /* 
    Since we can't say whenever this item can be NULL or cannot be NULL
    before mysql_stmt_execute(), so we assuming that it can be NULL until
    value is set.
  */
  maybe_null= 1;
unknown's avatar
unknown committed
2143 2144
  cnvitem= new Item_string("", 0, &my_charset_bin, DERIVATION_COERCIBLE);
  cnvstr.set(cnvbuf, sizeof(cnvbuf), &my_charset_bin);
2145
}
unknown's avatar
unknown committed
2146

2147

unknown's avatar
unknown committed
2148
void Item_param::set_null()
2149 2150
{
  DBUG_ENTER("Item_param::set_null");
2151
  /* These are cleared after each execution by reset() method */
2152 2153 2154 2155 2156 2157 2158 2159 2160
  null_value= 1;
  /* 
    Because of NULL and string values we need to set max_length for each new
    placeholder value: user can submit NULL for any placeholder type, and 
    string length can be different in each execution.
  */
  max_length= 0;
  decimals= 0;
  state= NULL_VALUE;
2161
  item_type= Item::NULL_ITEM;
2162
  DBUG_VOID_RETURN;
unknown's avatar
unknown committed
2163 2164
}

2165
void Item_param::set_int(longlong i, uint32 max_length_arg)
2166 2167
{
  DBUG_ENTER("Item_param::set_int");
2168 2169 2170 2171
  value.integer= (longlong) i;
  state= INT_VALUE;
  max_length= max_length_arg;
  decimals= 0;
2172
  maybe_null= 0;
2173
  DBUG_VOID_RETURN;
unknown's avatar
unknown committed
2174 2175
}

2176
void Item_param::set_double(double d)
2177 2178
{
  DBUG_ENTER("Item_param::set_double");
2179 2180 2181
  value.real= d;
  state= REAL_VALUE;
  max_length= DBL_DIG + 8;
2182
  decimals= NOT_FIXED_DEC;
2183
  maybe_null= 0;
2184
  DBUG_VOID_RETURN;
unknown's avatar
unknown committed
2185 2186 2187
}


unknown's avatar
unknown committed
2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200
/*
  Set decimal parameter value from string.

  SYNOPSIS
    set_decimal()
      str    - character string
      length - string length

  NOTE
    as we use character strings to send decimal values in
    binary protocol, we use str2my_decimal to convert it to
    internal decimal value.
*/
2201

unknown's avatar
unknown committed
2202 2203
void Item_param::set_decimal(const char *str, ulong length)
{
2204
  char *end;
unknown's avatar
unknown committed
2205 2206
  DBUG_ENTER("Item_param::set_decimal");

2207 2208
  end= (char*) str+length;
  str2my_decimal(E_DEC_FATAL_ERROR, str, &decimal_value, &end);
unknown's avatar
unknown committed
2209 2210
  state= DECIMAL_VALUE;
  decimals= decimal_value.frac;
unknown's avatar
unknown committed
2211 2212
  max_length= my_decimal_precision_to_length(decimal_value.precision(),
                                             decimals, unsigned_flag);
unknown's avatar
unknown committed
2213 2214 2215 2216 2217
  maybe_null= 0;
  DBUG_VOID_RETURN;
}


2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232
/*
  Set parameter value from TIME value.

  SYNOPSIS
    set_time()
      tm             - datetime value to set (time_type is ignored)
      type           - type of datetime value
      max_length_arg - max length of datetime value as string

  NOTE
    If we value to be stored is not normalized, zero value will be stored
    instead and proper warning will be produced. This function relies on
    the fact that even wrong value sent over binary protocol fits into
    MAX_DATE_STRING_REP_LENGTH buffer.
*/
2233
void Item_param::set_time(TIME *tm, timestamp_type type, uint32 max_length_arg)
2234
{ 
2235
  DBUG_ENTER("Item_param::set_time");
2236

2237 2238
  value.time= *tm;
  value.time.time_type= type;
2239

2240 2241 2242 2243 2244 2245 2246
  if (value.time.year > 9999 || value.time.month > 12 ||
      value.time.day > 31 ||
      type != MYSQL_TIMESTAMP_TIME && value.time.hour > 23 ||
      value.time.minute > 59 || value.time.second > 59)
  {
    char buff[MAX_DATE_STRING_REP_LENGTH];
    uint length= my_TIME_to_str(&value.time, buff);
unknown's avatar
unknown committed
2247
    make_truncated_value_warning(current_thd, buff, length, type, 0);
2248 2249 2250
    set_zero_time(&value.time, MYSQL_TIMESTAMP_ERROR);
  }

2251
  state= TIME_VALUE;
2252
  maybe_null= 0;
2253 2254
  max_length= max_length_arg;
  decimals= 0;
2255
  DBUG_VOID_RETURN;
unknown's avatar
unknown committed
2256 2257
}

2258

2259 2260 2261 2262 2263 2264 2265
bool Item_param::set_str(const char *str, ulong length)
{
  DBUG_ENTER("Item_param::set_str");
  /*
    Assign string with no conversion: data is converted only after it's
    been written to the binary log.
  */
2266 2267 2268
  uint dummy_errors;
  if (str_value.copy(str, length, &my_charset_bin, &my_charset_bin,
                     &dummy_errors))
2269 2270
    DBUG_RETURN(TRUE);
  state= STRING_VALUE;
unknown's avatar
unknown committed
2271
  max_length= length;
2272
  maybe_null= 0;
2273 2274 2275
  /* max_length and decimals are set after charset conversion */
  /* sic: str may be not null-terminated, don't add DBUG_PRINT here */
  DBUG_RETURN(FALSE);
2276 2277 2278
}


2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294
bool Item_param::set_longdata(const char *str, ulong length)
{
  DBUG_ENTER("Item_param::set_longdata");

  /*
    If client character set is multibyte, end of long data packet
    may hit at the middle of a multibyte character.  Additionally,
    if binary log is open we must write long data value to the
    binary log in character set of client. This is why we can't
    convert long data to connection character set as it comes
    (here), and first have to concatenate all pieces together,
    write query to the binary log and only then perform conversion.
  */
  if (str_value.append(str, length, &my_charset_bin))
    DBUG_RETURN(TRUE);
  state= LONG_DATA_VALUE;
2295
  maybe_null= 0;
2296 2297

  DBUG_RETURN(FALSE);
2298 2299 2300
}


2301 2302 2303 2304 2305 2306 2307 2308 2309 2310
/*
  Set parameter value from user variable value.

  SYNOPSIS
   set_from_user_var
     thd   Current thread
     entry User variable structure (NULL means use NULL value)

  RETURN
    0 OK
unknown's avatar
unknown committed
2311
    1 Out of memory
2312 2313 2314 2315 2316 2317 2318 2319
*/

bool Item_param::set_from_user_var(THD *thd, const user_var_entry *entry)
{
  DBUG_ENTER("Item_param::set_from_user_var");
  if (entry && entry->value)
  {
    item_result_type= entry->type;
unknown's avatar
unknown committed
2320 2321 2322
    switch (entry->type) {
    case REAL_RESULT:
      set_double(*(double*)entry->value);
2323 2324
      item_type= Item::REAL_ITEM;
      item_result_type= REAL_RESULT;
unknown's avatar
unknown committed
2325 2326 2327
      break;
    case INT_RESULT:
      set_int(*(longlong*)entry->value, 21);
2328 2329
      item_type= Item::INT_ITEM;
      item_result_type= INT_RESULT;
unknown's avatar
unknown committed
2330 2331
      break;
    case STRING_RESULT:
2332
    {
unknown's avatar
unknown committed
2333 2334 2335 2336
      CHARSET_INFO *fromcs= entry->collation.collation;
      CHARSET_INFO *tocs= thd->variables.collation_connection;
      uint32 dummy_offset;

2337
      value.cs_info.character_set_of_placeholder= fromcs;
unknown's avatar
unknown committed
2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356
      /*
        Setup source and destination character sets so that they
        are different only if conversion is necessary: this will
        make later checks easier.
      */
      value.cs_info.final_character_set_of_str_value=
        String::needs_conversion(0, fromcs, tocs, &dummy_offset) ?
        tocs : fromcs;
      /*
        Exact value of max_length is not known unless data is converted to
        charset of connection, so we have to set it later.
      */
      item_type= Item::STRING_ITEM;
      item_result_type= STRING_RESULT;

      if (set_str((const char *)entry->value, entry->length))
        DBUG_RETURN(1);
      break;
    }
unknown's avatar
unknown committed
2357 2358 2359 2360 2361 2362
    case DECIMAL_RESULT:
    {
      const my_decimal *ent_value= (const my_decimal *)entry->value;
      my_decimal2decimal(ent_value, &decimal_value);
      state= DECIMAL_VALUE;
      decimals= ent_value->frac;
unknown's avatar
unknown committed
2363 2364
      max_length= my_decimal_precision_to_length(ent_value->precision(),
                                                 decimals, unsigned_flag);
unknown's avatar
unknown committed
2365 2366
      break;
    }
unknown's avatar
unknown committed
2367 2368 2369
    default:
      DBUG_ASSERT(0);
      set_null();
2370 2371 2372 2373 2374 2375 2376 2377
    }
  }
  else
    set_null();

  DBUG_RETURN(0);
}

2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389
/*
    Resets parameter after execution.
  
  SYNOPSIS
     Item_param::reset()
 
  NOTES
    We clear null_value here instead of setting it in set_* methods, 
    because we want more easily handle case for long data.
*/

void Item_param::reset()
2390
{
2391
  DBUG_ENTER("Item_param::reset");
2392 2393 2394 2395 2396
  /* Shrink string buffer if it's bigger than max possible CHAR column */
  if (str_value.alloced_length() > MAX_CHAR_WIDTH)
    str_value.free();
  else
    str_value.length(0);
2397
  str_value_ptr.length(0);
2398
  /*
unknown's avatar
unknown committed
2399
    We must prevent all charset conversions until data has been written
2400
    to the binary log.
2401 2402
  */
  str_value.set_charset(&my_charset_bin);
2403
  collation.set(&my_charset_bin, DERIVATION_COERCIBLE);
2404
  state= NO_VALUE;
2405 2406
  maybe_null= 1;
  null_value= 0;
2407 2408 2409 2410 2411 2412 2413 2414 2415
  /*
    Don't reset item_type to PARAM_ITEM: it's only needed to guard
    us from item optimizations at prepare stage, when item doesn't yet
    contain a literal of some kind.
    In all other cases when this object is accessed its value is
    set (this assumption is guarded by 'state' and
    DBUG_ASSERTS(state != NO_VALUE) in all Item_param::get_*
    methods).
  */
2416
  DBUG_VOID_RETURN;
unknown's avatar
unknown committed
2417 2418 2419
}


unknown's avatar
unknown committed
2420
int Item_param::save_in_field(Field *field, bool no_conversions)
unknown's avatar
unknown committed
2421 2422
{
  field->set_notnull();
2423 2424 2425

  switch (state) {
  case INT_VALUE:
2426
    return field->store(value.integer, unsigned_flag);
2427 2428
  case REAL_VALUE:
    return field->store(value.real);
unknown's avatar
unknown committed
2429 2430
  case DECIMAL_VALUE:
    return field->store_decimal(&decimal_value);
2431 2432
  case TIME_VALUE:
    field->store_time(&value.time, value.time.time_type);
2433
    return 0;
2434 2435 2436 2437 2438
  case STRING_VALUE:
  case LONG_DATA_VALUE:
    return field->store(str_value.ptr(), str_value.length(),
                        str_value.charset());
  case NULL_VALUE:
2439
    return set_field_to_null_with_conversions(field, no_conversions);
2440 2441 2442
  case NO_VALUE:
  default:
    DBUG_ASSERT(0);
unknown's avatar
unknown committed
2443
  }
2444
  return 1;
unknown's avatar
unknown committed
2445 2446
}

2447

2448 2449
bool Item_param::get_time(TIME *res)
{
2450 2451 2452 2453 2454 2455 2456 2457 2458 2459
  if (state == TIME_VALUE)
  {
    *res= value.time;
    return 0;
  }
  /*
    If parameter value isn't supplied assertion will fire in val_str()
    which is called from Item::get_time().
  */
  return Item::get_time(res);
2460
}
2461

2462

2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473
bool Item_param::get_date(TIME *res, uint fuzzydate)
{
  if (state == TIME_VALUE)
  {
    *res= value.time;
    return 0;
  }
  return Item::get_date(res, fuzzydate);
}


2474
double Item_param::val_real()
unknown's avatar
unknown committed
2475
{
2476 2477 2478 2479 2480
  switch (state) {
  case REAL_VALUE:
    return value.real;
  case INT_VALUE:
    return (double) value.integer;
unknown's avatar
unknown committed
2481 2482 2483 2484 2485 2486
  case DECIMAL_VALUE:
  {
    double result;
    my_decimal2double(E_DEC_FATAL_ERROR, &decimal_value, &result);
    return result;
  }
2487 2488
  case STRING_VALUE:
  case LONG_DATA_VALUE:
2489 2490 2491 2492 2493 2494
  {
    int dummy_err;
    char *end_not_used;
    return my_strntod(str_value.charset(), (char*) str_value.ptr(),
                      str_value.length(), &end_not_used, &dummy_err);
  }
2495 2496 2497 2498 2499
  case TIME_VALUE:
    /*
      This works for example when user says SELECT ?+0.0 and supplies
      time value for the placeholder.
    */
2500
    return ulonglong2double(TIME_to_ulonglong(&value.time));
2501
  case NULL_VALUE:
2502
    return 0.0;
unknown's avatar
unknown committed
2503
  default:
2504
    DBUG_ASSERT(0);
unknown's avatar
unknown committed
2505
  }
2506
  return 0.0;
unknown's avatar
unknown committed
2507 2508
} 

2509

unknown's avatar
unknown committed
2510 2511
longlong Item_param::val_int() 
{ 
2512 2513
  switch (state) {
  case REAL_VALUE:
2514
    return (longlong) rint(value.real);
2515 2516
  case INT_VALUE:
    return value.integer;
unknown's avatar
unknown committed
2517 2518 2519 2520 2521 2522
  case DECIMAL_VALUE:
  {
    longlong i;
    my_decimal2int(E_DEC_FATAL_ERROR, &decimal_value, unsigned_flag, &i);
    return i;
  }
2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533
  case STRING_VALUE:
  case LONG_DATA_VALUE:
    {
      int dummy_err;
      return my_strntoll(str_value.charset(), str_value.ptr(),
                         str_value.length(), 10, (char**) 0, &dummy_err);
    }
  case TIME_VALUE:
    return (longlong) TIME_to_ulonglong(&value.time);
  case NULL_VALUE:
    return 0; 
unknown's avatar
unknown committed
2534
  default:
2535
    DBUG_ASSERT(0);
unknown's avatar
unknown committed
2536
  }
2537
  return 0;
unknown's avatar
unknown committed
2538 2539
}

2540

unknown's avatar
unknown committed
2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570
my_decimal *Item_param::val_decimal(my_decimal *dec)
{
  switch (state) {
  case DECIMAL_VALUE:
    return &decimal_value;
  case REAL_VALUE:
    double2my_decimal(E_DEC_FATAL_ERROR, value.real, dec);
    return dec;
  case INT_VALUE:
    int2my_decimal(E_DEC_FATAL_ERROR, value.integer, unsigned_flag, dec);
    return dec;
  case STRING_VALUE:
  case LONG_DATA_VALUE:
    string2my_decimal(E_DEC_FATAL_ERROR, &str_value, dec);
    return dec;
  case TIME_VALUE:
  {
    longlong i= (longlong) TIME_to_ulonglong(&value.time);
    int2my_decimal(E_DEC_FATAL_ERROR, i, 0, dec);
    return dec;
  }
  case NULL_VALUE:
    return 0; 
  default:
    DBUG_ASSERT(0);
  }
  return 0;
}


unknown's avatar
unknown committed
2571 2572
String *Item_param::val_str(String* str) 
{ 
2573 2574 2575
  switch (state) {
  case STRING_VALUE:
  case LONG_DATA_VALUE:
2576
    return &str_value_ptr;
2577 2578 2579 2580 2581
  case REAL_VALUE:
    str->set(value.real, NOT_FIXED_DEC, &my_charset_bin);
    return str;
  case INT_VALUE:
    str->set(value.integer, &my_charset_bin);
unknown's avatar
unknown committed
2582
    return str;
unknown's avatar
unknown committed
2583 2584 2585 2586 2587
  case DECIMAL_VALUE:
    if (my_decimal2string(E_DEC_FATAL_ERROR, &decimal_value,
                          0, 0, 0, str) <= 1)
      return str;
    return NULL;
2588 2589
  case TIME_VALUE:
  {
2590
    if (str->reserve(MAX_DATE_STRING_REP_LENGTH))
2591
      break;
2592 2593
    str->length((uint) my_TIME_to_str(&value.time, (char*) str->ptr()));
    str->set_charset(&my_charset_bin);
unknown's avatar
unknown committed
2594
    return str;
2595 2596 2597
  }
  case NULL_VALUE:
    return NULL; 
unknown's avatar
unknown committed
2598
  default:
2599
    DBUG_ASSERT(0);
unknown's avatar
unknown committed
2600
  }
2601
  return str;
unknown's avatar
unknown committed
2602
}
2603 2604 2605 2606

/*
  Return Param item values in string format, for generating the dynamic 
  query used in update/binary logs
2607 2608
  TODO: change interface and implementation to fill log data in place
  and avoid one more memcpy/alloc between str and log string.
2609 2610
*/

2611
const String *Item_param::query_val_str(String* str) const
2612
{
2613 2614 2615 2616 2617 2618 2619
  switch (state) {
  case INT_VALUE:
    str->set(value.integer, &my_charset_bin);
    break;
  case REAL_VALUE:
    str->set(value.real, NOT_FIXED_DEC, &my_charset_bin);
    break;
unknown's avatar
unknown committed
2620 2621 2622 2623 2624
  case DECIMAL_VALUE:
    if (my_decimal2string(E_DEC_FATAL_ERROR, &decimal_value,
                          0, 0, 0, str) > 1)
      return &my_null_string;
    break;
2625
  case TIME_VALUE:
2626
    {
2627 2628 2629 2630 2631 2632
      char *buf, *ptr;
      str->length(0);
      /*
        TODO: in case of error we need to notify replication
        that binary log contains wrong statement 
      */
2633
      if (str->reserve(MAX_DATE_STRING_REP_LENGTH+3))
2634 2635 2636 2637 2638 2639
        break; 

      /* Create date string inplace */
      buf= str->c_ptr_quick();
      ptr= buf;
      *ptr++= '\'';
2640
      ptr+= (uint) my_TIME_to_str(&value.time, ptr);
2641 2642 2643
      *ptr++= '\'';
      str->length((uint32) (ptr - buf));
      break;
2644
    }
2645 2646
  case STRING_VALUE:
  case LONG_DATA_VALUE:
2647
    {
2648 2649 2650 2651 2652 2653 2654
      char *buf, *ptr;
      str->length(0);
      if (str->reserve(str_value.length()*2+3))
        break;

      buf= str->c_ptr_quick();
      ptr= buf;
2655
      if (value.cs_info.character_set_client->escape_with_backslash_is_dangerous)
2656
      {
2657
        ptr= str_to_hex(ptr, str_value.ptr(), str_value.length());
2658 2659 2660 2661
      }
      else
      {
        *ptr++= '\'';
2662
        ptr+= escape_string_for_mysql(str_value.charset(), ptr, 0,
2663
                                      str_value.ptr(), str_value.length());
2664
        *ptr++='\'';
2665
      }
2666
      str->length((uint32) (ptr - buf));
2667
      break;
2668
    }
2669 2670 2671 2672
  case NULL_VALUE:
    return &my_null_string;
  default:
    DBUG_ASSERT(0);
2673 2674 2675
  }
  return str;
}
2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694


/*
  Convert string from client character set to the character set of
  connection.
*/

bool Item_param::convert_str_value(THD *thd)
{
  bool rc= FALSE;
  if (state == STRING_VALUE || state == LONG_DATA_VALUE)
  {
    /*
      Check is so simple because all charsets were set up properly
      in setup_one_conversion_function, where typecode of
      placeholder was also taken into account: the variables are different
      here only if conversion is really necessary.
    */
    if (value.cs_info.final_character_set_of_str_value !=
2695
        value.cs_info.character_set_of_placeholder)
2696 2697
    {
      rc= thd->convert_string(&str_value,
2698
                              value.cs_info.character_set_of_placeholder,
2699 2700
                              value.cs_info.final_character_set_of_str_value);
    }
2701 2702 2703 2704
    else
      str_value.set_charset(value.cs_info.final_character_set_of_str_value);
    /* Here str_value is guaranteed to be in final_character_set_of_str_value */

2705 2706
    max_length= str_value.length();
    decimals= 0;
2707 2708 2709 2710 2711 2712
    /*
      str_value_ptr is returned from val_str(). It must be not alloced
      to prevent it's modification by val_str() invoker.
    */
    str_value_ptr.set(str_value.ptr(), str_value.length(),
                      str_value.charset());
2713 2714
    /* Synchronize item charset with value charset */
    collation.set(str_value.charset(), DERIVATION_COERCIBLE);
2715 2716 2717 2718
  }
  return rc;
}

unknown's avatar
unknown committed
2719

2720 2721 2722 2723 2724 2725 2726
bool Item_param::basic_const_item() const
{
  if (state == NO_VALUE || state == TIME_VALUE)
    return FALSE;
  return TRUE;
}

unknown's avatar
unknown committed
2727

2728 2729 2730 2731 2732 2733 2734 2735
Item *
Item_param::new_item()
{
  /* see comments in the header file */
  switch (state) {
  case NULL_VALUE:
    return new Item_null(name);
  case INT_VALUE:
2736 2737 2738
    return (unsigned_flag ?
            new Item_uint(name, value.integer, max_length) :
            new Item_int(name, value.integer, max_length));
2739
  case REAL_VALUE:
2740
    return new Item_float(name, value.real, decimals, max_length);
2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773
  case STRING_VALUE:
  case LONG_DATA_VALUE:
    return new Item_string(name, str_value.c_ptr_quick(), str_value.length(),
                           str_value.charset());
  case TIME_VALUE:
    break;
  case NO_VALUE:
  default:
    DBUG_ASSERT(0);
  };
  return 0;
}


bool
Item_param::eq(const Item *arg, bool binary_cmp) const
{
  Item *item;
  if (!basic_const_item() || !arg->basic_const_item() || arg->type() != type())
    return FALSE;
  /*
    We need to cast off const to call val_int(). This should be OK for
    a basic constant.
  */
  item= (Item*) arg;

  switch (state) {
  case NULL_VALUE:
    return TRUE;
  case INT_VALUE:
    return value.integer == item->val_int() &&
           unsigned_flag == item->unsigned_flag;
  case REAL_VALUE:
2774
    return value.real == item->val_real();
2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785
  case STRING_VALUE:
  case LONG_DATA_VALUE:
    if (binary_cmp)
      return !stringcmp(&str_value, &item->str_value);
    return !sortcmp(&str_value, &item->str_value, collation.collation);
  default:
    break;
  }
  return FALSE;
}

unknown's avatar
unknown committed
2786 2787
/* End of Item_param related */

2788 2789 2790 2791 2792 2793 2794 2795
void Item_param::print(String *str)
{
  if (state == NO_VALUE)
  {
    str->append('?');
  }
  else
  {
unknown's avatar
unknown committed
2796
    char buffer[STRING_BUFFER_USUAL_SIZE];
2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807
    String tmp(buffer, sizeof(buffer), &my_charset_bin);
    const String *res;
    res= query_val_str(&tmp);
    str->append(*res);
  }
}


/****************************************************************************
  Item_copy_string
****************************************************************************/
2808

unknown's avatar
unknown committed
2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819
void Item_copy_string::copy()
{
  String *res=item->val_str(&str_value);
  if (res && res != &str_value)
    str_value.copy(*res);
  null_value=item->null_value;
}

/* ARGSUSED */
String *Item_copy_string::val_str(String *str)
{
2820
  // Item_copy_string is used without fix_fields call
unknown's avatar
unknown committed
2821 2822 2823 2824 2825
  if (null_value)
    return (String*) 0;
  return &str_value;
}

unknown's avatar
unknown committed
2826

unknown's avatar
unknown committed
2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837
my_decimal *Item_copy_string::val_decimal(my_decimal *decimal_value)
{
  // Item_copy_string is used without fix_fields call
  if (null_value)
    return 0;
  string2my_decimal(E_DEC_FATAL_ERROR, &str_value, decimal_value);
  return (decimal_value);
}



unknown's avatar
unknown committed
2838 2839 2840 2841 2842 2843 2844 2845 2846
int Item_copy_string::save_in_field(Field *field, bool no_conversions)
{
  if (null_value)
    return set_field_to_null(field);
  field->set_notnull();
  return field->store(str_value.ptr(),str_value.length(),
		      collation.collation);
}

unknown's avatar
unknown committed
2847
/*
2848
  Functions to convert item to field (for send_fields)
unknown's avatar
unknown committed
2849 2850 2851
*/

/* ARGSUSED */
2852
bool Item::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
2853
{
2854 2855

  // We do not check fields which are fixed during construction
unknown's avatar
unknown committed
2856
  DBUG_ASSERT(fixed == 0 || basic_const_item());
2857
  fixed= 1;
unknown's avatar
unknown committed
2858
  return FALSE;
unknown's avatar
unknown committed
2859 2860
}

2861
double Item_ref_null_helper::val_real()
2862
{
2863
  DBUG_ASSERT(fixed == 1);
2864
  double tmp= (*ref)->val_result();
unknown's avatar
unknown committed
2865
  owner->was_null|= null_value= (*ref)->null_value;
2866 2867
  return tmp;
}
2868 2869


2870 2871
longlong Item_ref_null_helper::val_int()
{
2872
  DBUG_ASSERT(fixed == 1);
2873
  longlong tmp= (*ref)->val_int_result();
unknown's avatar
unknown committed
2874
  owner->was_null|= null_value= (*ref)->null_value;
2875 2876
  return tmp;
}
2877 2878


unknown's avatar
unknown committed
2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896
my_decimal *Item_ref_null_helper::val_decimal(my_decimal *decimal_value)
{
  DBUG_ASSERT(fixed == 1);
  my_decimal *val= (*ref)->val_decimal_result(decimal_value);
  owner->was_null|= null_value= (*ref)->null_value;
  return val;
}


bool Item_ref_null_helper::val_bool()
{
  DBUG_ASSERT(fixed == 1);
  bool val= (*ref)->val_bool_result();
  owner->was_null|= null_value= (*ref)->null_value;
  return val;
}


2897 2898
String* Item_ref_null_helper::val_str(String* s)
{
2899
  DBUG_ASSERT(fixed == 1);
2900
  String* tmp= (*ref)->str_result(s);
unknown's avatar
unknown committed
2901
  owner->was_null|= null_value= (*ref)->null_value;
2902 2903
  return tmp;
}
2904 2905


2906
bool Item_ref_null_helper::get_date(TIME *ltime, uint fuzzydate)
2907 2908 2909
{  
  return (owner->was_null|= null_value= (*ref)->get_date(ltime, fuzzydate));
}
unknown's avatar
unknown committed
2910

unknown's avatar
unknown committed
2911 2912

/*
2913
  Mark item and SELECT_LEXs as dependent if item was resolved in outer SELECT
unknown's avatar
unknown committed
2914 2915 2916

  SYNOPSIS
    mark_as_dependent()
2917
    thd - thread handler
unknown's avatar
unknown committed
2918 2919
    last - select from which current item depend
    current  - current select
2920 2921 2922
    resolved_item - item which was resolved in outer SELECT(for warning)
    mark_item - item which should be marked (can be differ in case of
                substitution)
unknown's avatar
unknown committed
2923 2924
*/

2925
static void mark_as_dependent(THD *thd, SELECT_LEX *last, SELECT_LEX *current,
2926
                              Item_ident *resolved_item,
2927
                              Item_ident *mark_item)
unknown's avatar
unknown committed
2928
{
2929 2930 2931 2932
  const char *db_name= (resolved_item->db_name ?
                        resolved_item->db_name : "");
  const char *table_name= (resolved_item->table_name ?
                           resolved_item->table_name : "");
2933
  /* store pointer on SELECT_LEX from which item is dependent */
2934 2935
  if (mark_item)
    mark_item->depended_from= last;
unknown's avatar
unknown committed
2936
  current->mark_as_dependent(last);
unknown's avatar
unknown committed
2937
  if (thd->lex->describe & DESCRIBE_EXTENDED)
2938 2939 2940
  {
    char warn_buff[MYSQL_ERRMSG_SIZE];
    sprintf(warn_buff, ER(ER_WARN_FIELD_RESOLVED),
2941 2942
            db_name, (db_name[0] ? "." : ""),
            table_name, (table_name [0] ? "." : ""),
2943
            resolved_item->field_name,
2944 2945 2946 2947
	    current->select_number, last->select_number);
    push_warning(thd, MYSQL_ERROR::WARN_LEVEL_NOTE,
		 ER_WARN_FIELD_RESOLVED, warn_buff);
  }
unknown's avatar
unknown committed
2948 2949 2950
}


2951 2952 2953 2954 2955 2956 2957 2958
/*
  Mark range of selects and resolved identifier (field/reference) item as
  dependent

  SYNOPSIS
    mark_select_range_as_dependent()
    thd           - thread handler
    last_select   - select where resolved_item was resolved
unknown's avatar
unknown committed
2959
    current_sel   - current select (select where resolved_item was placed)
2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974
    found_field   - field which was found during resolving
    found_item    - Item which was found during resolving (if resolved
                    identifier belongs to VIEW)
    resolved_item - Identifier which was resolved

  NOTE:
    We have to mark all items between current_sel (including) and
    last_select (excluding) as dependend (select before last_select should
    be marked with actual table mask used by resolved item, all other with
    OUTER_REF_TABLE_BIT) and also write dependence information to Item of
    resolved identifier.
*/

void mark_select_range_as_dependent(THD *thd,
                                    SELECT_LEX *last_select,
unknown's avatar
unknown committed
2975
                                    SELECT_LEX *current_sel,
2976 2977 2978 2979 2980 2981 2982 2983 2984 2985
                                    Field *found_field, Item *found_item,
                                    Item_ident *resolved_item)
{
  /*
    Go from current SELECT to SELECT where field was resolved (it
    have to be reachable from current SELECT, because it was already
    done once when we resolved this field and cached result of
    resolving)
  */
  SELECT_LEX *previous_select= current_sel;
unknown's avatar
unknown committed
2986 2987
  for (; previous_select->outer_select() != last_select;
       previous_select= previous_select->outer_select())
2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014
  {
    Item_subselect *prev_subselect_item=
      previous_select->master_unit()->item;
    prev_subselect_item->used_tables_cache|= OUTER_REF_TABLE_BIT;
    prev_subselect_item->const_item_cache= 0;
  }
  {
    Item_subselect *prev_subselect_item=
      previous_select->master_unit()->item;
    Item_ident *dependent= resolved_item;
    if (found_field == view_ref_found)
    {
      Item::Type type= found_item->type();
      prev_subselect_item->used_tables_cache|=
        found_item->used_tables();
      dependent= ((type == Item::REF_ITEM || type == Item::FIELD_ITEM) ?
                  (Item_ident*) found_item :
                  0);
    }
    else
      prev_subselect_item->used_tables_cache|=
        found_field->table->map;
    prev_subselect_item->const_item_cache= 0;
    mark_as_dependent(thd, last_select, current_sel, resolved_item,
                      dependent);
  }
}
3015 3016


3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041
/*
  Search a GROUP BY clause for a field with a certain name.

  SYNOPSIS
    find_field_in_group_list()
    find_item  the item being searched for
    group_list GROUP BY clause

  DESCRIPTION
    Search the GROUP BY list for a column named as find_item. When searching
    preference is given to columns that are qualified with the same table (and
    database) name as the one being searched for.

  RETURN
    - the found item on success
    - NULL if find_item is not in group_list
*/

static Item** find_field_in_group_list(Item *find_item, ORDER *group_list)
{
  const char *db_name;
  const char *table_name;
  const char *field_name;
  ORDER      *found_group= NULL;
  int         found_match_degree= 0;
3042
  Item_ident *cur_field;
3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054
  int         cur_match_degree= 0;

  if (find_item->type() == Item::FIELD_ITEM ||
      find_item->type() == Item::REF_ITEM)
  {
    db_name=    ((Item_ident*) find_item)->db_name;
    table_name= ((Item_ident*) find_item)->table_name;
    field_name= ((Item_ident*) find_item)->field_name;
  }
  else
    return NULL;

3055
  DBUG_ASSERT(field_name != 0);
3056 3057 3058

  for (ORDER *cur_group= group_list ; cur_group ; cur_group= cur_group->next)
  {
unknown's avatar
unknown committed
3059
    if ((*(cur_group->item))->real_item()->type() == Item::FIELD_ITEM)
3060
    {
3061
      cur_field= (Item_ident*) *cur_group->item;
3062 3063
      cur_match_degree= 0;
      
3064
      DBUG_ASSERT(cur_field->field_name != 0);
3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102

      if (!my_strcasecmp(system_charset_info,
                         cur_field->field_name, field_name))
        ++cur_match_degree;
      else
        continue;

      if (cur_field->table_name && table_name)
      {
        /* If field_name is qualified by a table name. */
        if (strcmp(cur_field->table_name, table_name))
          /* Same field names, different tables. */
          return NULL;

        ++cur_match_degree;
        if (cur_field->db_name && db_name)
        {
          /* If field_name is also qualified by a database name. */
          if (strcmp(cur_field->db_name, db_name))
            /* Same field names, different databases. */
            return NULL;
          ++cur_match_degree;
        }
      }

      if (cur_match_degree > found_match_degree)
      {
        found_match_degree= cur_match_degree;
        found_group= cur_group;
      }
      else if (found_group && (cur_match_degree == found_match_degree) &&
               ! (*(found_group->item))->eq(cur_field, 0))
      {
        /*
          If the current resolve candidate matches equally well as the current
          best match, they must reference the same column, otherwise the field
          is ambiguous.
        */
3103 3104
        my_error(ER_NON_UNIQ_ERROR, MYF(0),
                 find_item->full_name(), current_thd->where);
3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160
        return NULL;
      }
    }
  }

  if (found_group)
    return found_group->item;
  else
    return NULL;
}


/*
  Resolve a column reference in a sub-select.

  SYNOPSIS
    resolve_ref_in_select_and_group()
    thd     current thread
    ref     column reference being resolved
    select  the sub-select that ref is resolved against

  DESCRIPTION
    Resolve a column reference (usually inside a HAVING clause) against the
    SELECT and GROUP BY clauses of the query described by 'select'. The name
    resolution algorithm searches both the SELECT and GROUP BY clauses, and in
    case of a name conflict prefers GROUP BY column names over SELECT names. If
    both clauses contain different fields with the same names, a warning is
    issued that name of 'ref' is ambiguous. We extend ANSI SQL in that when no
    GROUP BY column is found, then a HAVING name is resolved as a possibly
    derived SELECT column.

  NOTES
    The resolution procedure is:
    - Search for a column or derived column named col_ref_i [in table T_j]
      in the SELECT clause of Q.
    - Search for a column named col_ref_i [in table T_j]
      in the GROUP BY clause of Q.
    - If found different columns with the same name in GROUP BY and SELECT
      - issue a warning and return the GROUP BY column,
      - otherwise return the found SELECT column.


  RETURN
    NULL - there was an error, and the error was already reported
    not_found_item - the item was not resolved, no error was reported
    resolved item - if the item was resolved
*/

static Item**
resolve_ref_in_select_and_group(THD *thd, Item_ident *ref, SELECT_LEX *select)
{
  Item **group_by_ref= NULL;
  Item **select_ref= NULL;
  ORDER *group_list= (ORDER*) select->group_list.first;
  bool ambiguous_fields= FALSE;
  uint counter;
3161
  bool not_used;
3162 3163 3164 3165 3166

  /*
    Search for a column or derived column named as 'ref' in the SELECT
    clause of the current select.
  */
3167 3168 3169
  if (!(select_ref= find_item_in_list(ref, *(select->get_item_list()),
                                      &counter, REPORT_EXCEPT_NOT_FOUND,
                                      &not_used)))
3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192
    return NULL; /* Some error occurred. */

  /* If this is a non-aggregated field inside HAVING, search in GROUP BY. */
  if (select->having_fix_field && !ref->with_sum_func && group_list)
  {
    group_by_ref= find_field_in_group_list(ref, group_list);
    
    /* Check if the fields found in SELECT and GROUP BY are the same field. */
    if (group_by_ref && (select_ref != not_found_item) &&
        !((*group_by_ref)->eq(*select_ref, 0)))
    {
      ambiguous_fields= TRUE;
      push_warning_printf(thd, MYSQL_ERROR::WARN_LEVEL_WARN, ER_NON_UNIQ_ERROR,
                          ER(ER_NON_UNIQ_ERROR), ref->full_name(),
                          current_thd->where);

    }
  }

  if (select_ref != not_found_item || group_by_ref)
  {
    if (select_ref != not_found_item && !ambiguous_fields)
    {
3193
      DBUG_ASSERT(*select_ref != 0);
unknown's avatar
unknown committed
3194
      if (!select->ref_pointer_array[counter])
3195
      {
3196 3197
        my_error(ER_ILLEGAL_REFERENCE, MYF(0),
                 ref->name, "forward reference in item list");
3198 3199
        return NULL;
      }
unknown's avatar
unknown committed
3200
      DBUG_ASSERT((*select_ref)->fixed);
3201 3202
      return (select->ref_pointer_array + counter);
    }
unknown's avatar
unknown committed
3203
    if (group_by_ref)
3204
      return group_by_ref;
unknown's avatar
unknown committed
3205 3206
    DBUG_ASSERT(FALSE);
    return NULL; /* So there is no compiler warning. */
3207
  }
unknown's avatar
unknown committed
3208 3209

  return (Item**) not_found_item;
3210 3211 3212
}


3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239
/*
  Resolve the name of a column reference.

  SYNOPSIS
    Item_field::fix_fields()
    thd       [in]      current thread
    reference [in/out]  view column if this item was resolved to a view column

  DESCRIPTION
    The method resolves the column reference represented by 'this' as a column
    present in one of: FROM clause, SELECT clause, GROUP BY clause of a query
    Q, or in outer queries that contain Q.

  NOTES
    The name resolution algorithm used is (where [T_j] is an optional table
    name that qualifies the column name):

      resolve_column_reference([T_j].col_ref_i)
      {
        search for a column or derived column named col_ref_i
        [in table T_j] in the FROM clause of Q;

        if such a column is NOT found AND    // Lookup in outer queries.
           there are outer queries
        {
          for each outer query Q_k beginning from the inner-most one
          {
unknown's avatar
unknown committed
3240 3241
            search for a column or derived column named col_ref_i
            [in table T_j] in the FROM clause of Q_k;
3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257

            if such a column is not found
              Search for a column or derived column named col_ref_i
              [in table T_j] in the SELECT and GROUP clauses of Q_k.
          }
        }
      }

    Notice that compared to Item_ref::fix_fields, here we first search the FROM
    clause, and then we search the SELECT and GROUP BY clauses.

  RETURN
    TRUE  if error
    FALSE on success
*/

3258
bool Item_field::fix_fields(THD *thd, Item **reference)
unknown's avatar
unknown committed
3259
{
3260
  enum_parsing_place place= NO_MATTER;
unknown's avatar
unknown committed
3261
  DBUG_ASSERT(fixed == 0);
3262
  if (!field)					// If field is not checked
unknown's avatar
unknown committed
3263
  {
3264 3265
    bool upward_lookup= FALSE;
    Field *from_field= (Field *)not_found_field;
3266 3267 3268 3269 3270
    /*
      In case of view, find_field_in_tables() write pointer to view field
      expression to 'reference', i.e. it substitute that expression instead
      of this Item_field
    */
unknown's avatar
unknown committed
3271 3272 3273
    if ((from_field= find_field_in_tables(thd, this,
                                          context->first_name_resolution_table,
                                          context->last_name_resolution_table,
3274 3275
                                          reference,
                                          IGNORE_EXCEPT_NON_UNIQUE,
3276
                                          !any_privileges,
3277
                                          TRUE)) ==
3278
	not_found_field)
3279
    {
unknown's avatar
unknown committed
3280 3281 3282 3283 3284 3285 3286 3287 3288

      /* Look up in current select's item_list to find aliased fields */
      if (thd->lex->current_select->is_item_list_lookup)
      {
        uint counter;
        bool not_used;
        Item** res= find_item_in_list(this, thd->lex->current_select->item_list,
                                      &counter, REPORT_EXCEPT_NOT_FOUND,
                                      &not_used);
3289
        if (res != (Item **)not_found_item && (*res)->type() == Item::FIELD_ITEM)
unknown's avatar
unknown committed
3290 3291 3292
        {
          set_field((*((Item_field**)res))->field);
          return 0;
3293 3294
        }
      }
unknown's avatar
unknown committed
3295

3296
      /*
unknown's avatar
unknown committed
3297
        If there are outer contexts (outer selects, but current select is
3298 3299 3300
        not derived table or view) try to resolve this reference in the
        outer contexts.

3301
        We treat each subselect as a separate namespace, so that different
unknown's avatar
unknown committed
3302 3303
        subselects may contain columns with the same names. The subselects
        are searched starting from the innermost.
3304
      */
3305 3306 3307 3308 3309 3310
      Name_resolution_context *last_checked_context= context;
      Item **ref= (Item **) not_found_item;
      Name_resolution_context *outer_context= context->outer_context;
      for (;
           outer_context;
           outer_context= outer_context->outer_context)
3311
      {
3312 3313 3314 3315 3316
        SELECT_LEX *select= outer_context->select_lex;
        Item_subselect *prev_subselect_item=
          last_checked_context->select_lex->master_unit()->item;
        last_checked_context= outer_context;
        upward_lookup= TRUE;
3317

3318 3319 3320 3321 3322 3323
        place= prev_subselect_item->parsing_place;
        /*
          In case of a view, find_field_in_tables() writes the pointer to
          the found view field into '*reference', in other words, it
          substitutes this Item_field with the found expression.
        */
unknown's avatar
unknown committed
3324
        if ((from_field= find_field_in_tables(thd, this,
unknown's avatar
unknown committed
3325 3326 3327 3328
                                              outer_context->
                                                first_name_resolution_table,
                                              outer_context->
                                                last_name_resolution_table,
3329 3330
                                              reference,
                                              IGNORE_EXCEPT_NON_UNIQUE,
3331
                                              TRUE, TRUE)) !=
3332 3333 3334
            not_found_field)
        {
          if (from_field)
unknown's avatar
unknown committed
3335
          {
3336
            if (from_field != view_ref_found)
3337
            {
3338 3339
              prev_subselect_item->used_tables_cache|= from_field->table->map;
              prev_subselect_item->const_item_cache= 0;
unknown's avatar
unknown committed
3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354
              if (thd->lex->in_sum_func &&
                  thd->lex->in_sum_func->nest_level == 
                  thd->lex->current_select->nest_level)
              {
                Item::Type type= (*reference)->type();
                set_if_bigger(thd->lex->in_sum_func->max_arg_level,
                              select->nest_level);
                set_field(from_field);
                fixed= 1;
                mark_as_dependent(thd, last_checked_context->select_lex,
                                  context->select_lex, this,
                                  ((type == REF_ITEM || type == FIELD_ITEM) ?
                                   (Item_ident*) (*reference) : 0));
                return FALSE;
              }
3355
            }
3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378
            else
            {
              Item::Type type= (*reference)->type();
              prev_subselect_item->used_tables_cache|=
                (*reference)->used_tables();
              prev_subselect_item->const_item_cache&=
                (*reference)->const_item();
              mark_as_dependent(thd, last_checked_context->select_lex,
                                context->select_lex, this,
                                ((type == REF_ITEM || type == FIELD_ITEM) ?
                                 (Item_ident*) (*reference) :
                                 0));
              /*
                A reference to a view field had been found and we
                substituted it instead of this Item (find_field_in_tables
                does it by assigning the new value to *reference), so now
                we can return from this function.
              */
              return FALSE;
            }
          }
          break;
        }
3379

3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392
        /* Search in SELECT and GROUP lists of the outer select. */
        if (outer_context->resolve_in_select_list)
        {
          if (!(ref= resolve_ref_in_select_and_group(thd, this, select)))
            goto error; /* Some error occurred (e.g. ambiguous names). */
          if (ref != not_found_item)
          {
            DBUG_ASSERT(*ref && (*ref)->fixed);
            prev_subselect_item->used_tables_cache|= (*ref)->used_tables();
	    prev_subselect_item->const_item_cache&= (*ref)->const_item();
            break;
          }
        }
3393

3394 3395 3396 3397 3398 3399 3400
        /*
          Reference is not found in this select => this subquery depend on
          outer select (or we just trying to find wrong identifier, in this
          case it does not matter which used tables bits we set)
        */
        prev_subselect_item->used_tables_cache|= OUTER_REF_TABLE_BIT;
        prev_subselect_item->const_item_cache= 0;
3401
      }
3402

3403
      DBUG_ASSERT(ref != 0);
3404
      if (!from_field)
3405
	goto error;
3406
      if (ref == not_found_item && from_field == not_found_field)
unknown's avatar
unknown committed
3407
      {
3408
	if (upward_lookup)
unknown's avatar
unknown committed
3409
	{
3410
          // We can't say exactly what absent table or field
3411
	  my_error(ER_BAD_FIELD_ERROR, MYF(0), full_name(), thd->where);
unknown's avatar
unknown committed
3412
	}
3413
	else
unknown's avatar
unknown committed
3414
	{
3415
          /* Call find_field_in_tables only to report the error */
unknown's avatar
unknown committed
3416 3417 3418
	  find_field_in_tables(thd, this,
                               context->first_name_resolution_table,
                               context->last_name_resolution_table,
3419 3420
                               reference, REPORT_ALL_ERRORS,
                               !any_privileges &&
3421
                               TRUE, TRUE);
unknown's avatar
unknown committed
3422
	}
3423
	goto error;
unknown's avatar
unknown committed
3424
      }
3425
      else if (ref != not_found_item)
3426
      {
unknown's avatar
unknown committed
3427 3428 3429
        Item *save;
        Item_ref *rf;

3430
        /* Should have been checked in resolve_ref_in_select_and_group(). */
3431
        DBUG_ASSERT(*ref && (*ref)->fixed);
3432 3433
        /*
          Here, a subset of actions performed by Item_ref::set_properties
unknown's avatar
unknown committed
3434 3435 3436
          is not enough. So we pass ptr to NULL into Item_[direct]_ref
          constructor, so no initialization is performed, and call 
          fix_fields() below.
3437
        */
unknown's avatar
unknown committed
3438 3439 3440
        save= *ref;
        *ref= NULL;                             // Don't call set_properties()
        rf= (place == IN_HAVING ?
3441 3442 3443 3444
             new Item_ref(context, ref, (char*) table_name,
                          (char*) field_name) :
             new Item_direct_ref(context, ref, (char*) table_name,
                                 (char*) field_name));
unknown's avatar
unknown committed
3445
        *ref= save;
unknown's avatar
unknown committed
3446
	if (!rf)
3447
	  goto error;
3448
        thd->change_item_tree(reference, rf);
3449 3450 3451 3452
	/*
	  rf is Item_ref => never substitute other items (in this case)
	  during fix_fields() => we can use rf after fix_fields()
	*/
3453
        DBUG_ASSERT(!rf->fixed);                // Assured by Item_ref()
3454 3455
        if (rf->fix_fields(thd, reference) || rf->check_cols(1))
	  goto error;
unknown's avatar
unknown committed
3456

3457 3458 3459
	mark_as_dependent(thd, last_checked_context->select_lex,
                          context->select_lex, this,
                          rf);
3460
	return FALSE;
3461
      }
3462
      else
unknown's avatar
unknown committed
3463
      {
3464 3465 3466 3467
	mark_as_dependent(thd, last_checked_context->select_lex,
                          context->select_lex,
                          this, this);
	if (last_checked_context->select_lex->having_fix_field)
3468 3469
	{
	  Item_ref *rf;
3470 3471
          rf= new Item_ref(context,
                           (cached_table->db[0] ? cached_table->db : 0),
3472
                           (char*) cached_table->alias, (char*) field_name);
3473
	  if (!rf)
3474
	    goto error;
3475
          thd->change_item_tree(reference, rf);
3476 3477 3478 3479
	  /*
	    rf is Item_ref => never substitute other items (in this case)
	    during fix_fields() => we can use rf after fix_fields()
	  */
3480
          DBUG_ASSERT(!rf->fixed);                // Assured by Item_ref()
3481 3482 3483
          if (rf->fix_fields(thd, reference) || rf->check_cols(1))
            goto error;
          return FALSE;
3484
	}
unknown's avatar
unknown committed
3485
      }
3486
    }
3487
    else if (!from_field)
3488
      goto error;
3489

unknown's avatar
VIEW  
unknown committed
3490 3491 3492 3493 3494 3495
    /*
      if it is not expression from merged VIEW we will set this field.

      We can leave expression substituted from view for next PS/SP rexecution
      (i.e. do not register this substitution for reverting on cleupup()
      (register_item_tree_changing())), because this subtree will be
3496
      fix_field'ed during setup_tables()->setup_underlying() (i.e. before
unknown's avatar
VIEW  
unknown committed
3497 3498 3499 3500 3501
      all other expressions of query, and references on tables which do
      not present in query will not make problems.

      Also we suppose that view can't be changed during PS/SP life.
    */
3502 3503 3504 3505
    if (from_field == view_ref_found)
      return FALSE;

    set_field(from_field);
unknown's avatar
unknown committed
3506 3507 3508 3509 3510
    if (thd->lex->in_sum_func &&
        thd->lex->in_sum_func->nest_level == 
        thd->lex->current_select->nest_level)
      set_if_bigger(thd->lex->in_sum_func->max_arg_level,
                    thd->lex->current_select->nest_level);
unknown's avatar
unknown committed
3511
  }
unknown's avatar
unknown committed
3512
  else if (thd->set_query_id && field->query_id != thd->query_id)
3513 3514 3515 3516 3517
  {
    /* We only come here in unions */
    TABLE *table=field->table;
    field->query_id=thd->query_id;
    table->used_fields++;
3518
    table->used_keys.intersect(field->part_of_key);
3519
  }
unknown's avatar
VIEW  
unknown committed
3520 3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531
#ifndef NO_EMBEDDED_ACCESS_CHECKS
  if (any_privileges)
  {
    char *db, *tab;
    if (cached_table->view)
    {
      db= cached_table->view_db.str;
      tab= cached_table->view_name.str;
    }
    else
    {
      db= cached_table->db;
3532
      tab= cached_table->table_name;
unknown's avatar
VIEW  
unknown committed
3533 3534 3535 3536 3537
    }
    if (!(have_privileges= (get_column_grant(thd, &field->table->grant,
                                             db, tab, field_name) &
                            VIEW_ANY_ACL)))
    {
3538
      my_error(ER_COLUMNACCESS_DENIED_ERROR, MYF(0),
3539 3540
               "ANY", thd->security_ctx->priv_user,
               thd->security_ctx->host_or_ip, field_name, tab);
3541
      goto error;
unknown's avatar
VIEW  
unknown committed
3542 3543 3544
    }
  }
#endif
3545
  fixed= 1;
3546
  return FALSE;
3547 3548 3549 3550

error:
  context->process_error(thd);
  return TRUE;
unknown's avatar
unknown committed
3551 3552
}

3553 3554 3555 3556 3557 3558 3559 3560

Item *Item_field::safe_charset_converter(CHARSET_INFO *tocs)
{
  no_const_subst= 1;
  return Item::safe_charset_converter(tocs);
}


unknown's avatar
unknown committed
3561 3562
void Item_field::cleanup()
{
unknown's avatar
unknown committed
3563
  DBUG_ENTER("Item_field::cleanup");
unknown's avatar
unknown committed
3564
  Item_ident::cleanup();
3565 3566
  /*
    Even if this object was created by direct link to field in setup_wild()
unknown's avatar
unknown committed
3567
    it will be linked correctly next time by name of field and table alias.
3568 3569
    I.e. we can drop 'field'.
   */
3570
  field= result_field= 0;
3571
  DBUG_VOID_RETURN;
3572
}
unknown's avatar
unknown committed
3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593

/*
  Find a field among specified multiple equalities 

  SYNOPSIS
    find_item_equal()
    cond_equal   reference to list of multiple equalities where
                 the field (this object) is to be looked for
  
  DESCRIPTION
    The function first searches the field among multiple equalities
    of the current level (in the cond_equal->current_level list).
    If it fails, it continues searching in upper levels accessed
    through a pointer cond_equal->upper_levels.
    The search terminates as soon as a multiple equality containing 
    the field is found. 

  RETURN VALUES
    First Item_equal containing the field, if success
    0, otherwise
*/
unknown's avatar
unknown committed
3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615
Item_equal *Item_field::find_item_equal(COND_EQUAL *cond_equal)
{
  Item_equal *item= 0;
  while (cond_equal)
  {
    List_iterator_fast<Item_equal> li(cond_equal->current_level);
    while ((item= li++))
    {
      if (item->contains(field))
        return item;
    }
    /* 
      The field is not found in any of the multiple equalities
      of the current level. Look for it in upper levels
    */
    cond_equal= cond_equal->upper_levels;
  }
  return 0;
}


/*
3616 3617
  Set a pointer to the multiple equality the field reference belongs to
  (if any)
unknown's avatar
unknown committed
3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639
   
  SYNOPSIS
    equal_fields_propagator()
    arg - reference to list of multiple equalities where
          the field (this object) is to be looked for
  
  DESCRIPTION
    The function looks for a multiple equality containing the field item
    among those referenced by arg.
    In the case such equality exists the function does the following.
    If the found multiple equality contains a constant, then the field
    reference is substituted for this constant, otherwise it sets a pointer
    to the multiple equality in the field item.

  NOTES
    This function is supposed to be called as a callback parameter in calls
    of the transform method.  

  RETURN VALUES
    pointer to the replacing constant item, if the field item was substituted 
    pointer to the field item, otherwise.
*/
unknown's avatar
unknown committed
3640

unknown's avatar
unknown committed
3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655
Item *Item_field::equal_fields_propagator(byte *arg)
{
  if (no_const_subst)
    return this;
  item_equal= find_item_equal((COND_EQUAL *) arg);
  Item *item= 0;
  if (item_equal)
    item= item_equal->get_const();
  if (!item)
    item= this;
  return item;
}


/*
3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668
  Mark the item to not be part of substitution if it's not a binary item
  See comments in Arg_comparator::set_compare_func() for details
*/

Item *Item_field::set_no_const_sub(byte *arg)
{
  if (field->charset() != &my_charset_bin)
    no_const_subst=1;
  return this;
}


/*
unknown's avatar
unknown committed
3669
  Replace an Item_field for an equal Item_field that evaluated earlier
3670
  (if any)
unknown's avatar
unknown committed
3671 3672
   
  SYNOPSIS
unknown's avatar
unknown committed
3673
    replace_equal_field_()
unknown's avatar
unknown committed
3674 3675 3676
    arg - a dummy parameter, is not used here
  
  DESCRIPTION
unknown's avatar
unknown committed
3677 3678 3679 3680 3681
    The function returns a pointer to an item that is taken from
    the very beginning of the item_equal list which the Item_field
    object refers to (belongs to).  
    If the Item_field object does not refer any Item_equal object
    'this' is returned 
unknown's avatar
unknown committed
3682 3683 3684

  NOTES
    This function is supposed to be called as a callback parameter in calls
unknown's avatar
unknown committed
3685
    of the thransformer method.  
unknown's avatar
unknown committed
3686 3687

  RETURN VALUES
unknown's avatar
unknown committed
3688 3689
    pointer to a replacement Item_field if there is a better equal item;
    this - otherwise.
unknown's avatar
unknown committed
3690 3691
*/

unknown's avatar
unknown committed
3692
Item *Item_field::replace_equal_field(byte *arg)
unknown's avatar
unknown committed
3693 3694 3695 3696 3697
{
  if (item_equal)
  {
    Item_field *subst= item_equal->get_first();
    if (!field->eq(subst->field))
unknown's avatar
unknown committed
3698
      return subst;
unknown's avatar
unknown committed
3699
  }
unknown's avatar
unknown committed
3700
  return this;
unknown's avatar
unknown committed
3701
}
unknown's avatar
unknown committed
3702

3703

unknown's avatar
unknown committed
3704 3705
void Item::init_make_field(Send_field *tmp_field,
			   enum enum_field_types field_type)
3706
{
3707
  char *empty_name= (char*) "";
3708
  tmp_field->db_name=		empty_name;
3709 3710 3711 3712
  tmp_field->org_table_name=	empty_name;
  tmp_field->org_col_name=	empty_name;
  tmp_field->table_name=	empty_name;
  tmp_field->col_name=		name;
3713
  tmp_field->charsetnr=         collation.collation->number;
3714 3715 3716
  tmp_field->flags=             (maybe_null ? 0 : NOT_NULL_FLAG) | 
                                (my_binary_compare(collation.collation) ?
                                 BINARY_FLAG : 0);
unknown's avatar
unknown committed
3717 3718 3719
  tmp_field->type=field_type;
  tmp_field->length=max_length;
  tmp_field->decimals=decimals;
3720 3721
  if (unsigned_flag)
    tmp_field->flags |= UNSIGNED_FLAG;
unknown's avatar
unknown committed
3722 3723
}

3724
void Item::make_field(Send_field *tmp_field)
unknown's avatar
unknown committed
3725
{
3726
  init_make_field(tmp_field, field_type());
unknown's avatar
unknown committed
3727 3728 3729
}


3730 3731
void Item_empty_string::make_field(Send_field *tmp_field)
{
3732 3733 3734 3735 3736
  enum_field_types type= FIELD_TYPE_VAR_STRING;
  if (max_length >= 16777216)
    type= FIELD_TYPE_LONG_BLOB;
  else if (max_length >= 65536)
    type= FIELD_TYPE_MEDIUM_BLOB;
3737
  init_make_field(tmp_field, type);
3738 3739
}

unknown's avatar
unknown committed
3740

3741
enum_field_types Item::field_type() const
unknown's avatar
unknown committed
3742
{
3743
  switch (result_type()) {
unknown's avatar
unknown committed
3744 3745 3746 3747 3748 3749 3750
  case STRING_RESULT:  return MYSQL_TYPE_VARCHAR;
  case INT_RESULT:     return FIELD_TYPE_LONGLONG;
  case DECIMAL_RESULT: return FIELD_TYPE_NEWDECIMAL;
  case REAL_RESULT:    return FIELD_TYPE_DOUBLE;
  case ROW_RESULT:
  default:
    DBUG_ASSERT(0);
3751 3752
    return MYSQL_TYPE_VARCHAR;
  }
unknown's avatar
unknown committed
3753 3754
}

3755

3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771
/*
  Create a field to hold a string value from an item

  SYNOPSIS
    make_string_field()
    table		Table for which the field is created

  IMPLEMENTATION
    If max_length > CONVERT_IF_BIGGER_TO_BLOB create a blob
    If max_length > 0 create a varchar
    If max_length == 0 create a CHAR(0) 
*/


Field *Item::make_string_field(TABLE *table)
{
3772 3773
  DBUG_ASSERT(collation.collation);
  if (max_length/collation.collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB)
3774 3775 3776 3777 3778 3779 3780 3781 3782 3783
    return new Field_blob(max_length, maybe_null, name, table,
                          collation.collation);
  if (max_length > 0)
    return new Field_varstring(max_length, maybe_null, name, table,
                               collation.collation);
  return new Field_string(max_length, maybe_null, name, table,
                          collation.collation);
}


3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794
/*
  Create a field based on field_type of argument

  For now, this is only used to create a field for
  IFNULL(x,something)

  RETURN
    0  error
    #  Created field
*/

3795 3796
Field *Item::tmp_table_field_from_field_type(TABLE *table)
{
3797 3798 3799 3800 3801 3802
  /*
    The field functions defines a field to be not null if null_ptr is not 0
  */
  uchar *null_ptr= maybe_null ? (uchar*) "" : 0;

  switch (field_type()) {
3803
  case MYSQL_TYPE_DECIMAL:
unknown's avatar
unknown committed
3804
  case MYSQL_TYPE_NEWDECIMAL:
unknown's avatar
unknown committed
3805
    return new Field_new_decimal((char*) 0, max_length, null_ptr, 0,
unknown's avatar
unknown committed
3806 3807
                                 Field::NONE, name, table, decimals, 0,
                                 unsigned_flag);
3808
  case MYSQL_TYPE_TINY:
3809 3810
    return new Field_tiny((char*) 0, max_length, null_ptr, 0, Field::NONE,
			  name, table, 0, unsigned_flag);
3811
  case MYSQL_TYPE_SHORT:
3812 3813
    return new Field_short((char*) 0, max_length, null_ptr, 0, Field::NONE,
			   name, table, 0, unsigned_flag);
3814
  case MYSQL_TYPE_LONG:
3815 3816
    return new Field_long((char*) 0, max_length, null_ptr, 0, Field::NONE,
			  name, table, 0, unsigned_flag);
3817 3818
#ifdef HAVE_LONG_LONG
  case MYSQL_TYPE_LONGLONG:
3819 3820
    return new Field_longlong((char*) 0, max_length, null_ptr, 0, Field::NONE,
			      name, table, 0, unsigned_flag);
3821
#endif
3822 3823 3824 3825 3826 3827 3828 3829 3830
  case MYSQL_TYPE_FLOAT:
    return new Field_float((char*) 0, max_length, null_ptr, 0, Field::NONE,
			   name, table, decimals, 0, unsigned_flag);
  case MYSQL_TYPE_DOUBLE:
    return new Field_double((char*) 0, max_length, null_ptr, 0, Field::NONE,
			    name, table, decimals, 0, unsigned_flag);
  case MYSQL_TYPE_NULL:
    return new Field_null((char*) 0, max_length, Field::NONE,
			  name, table, &my_charset_bin);
3831
  case MYSQL_TYPE_INT24:
3832 3833
    return new Field_medium((char*) 0, max_length, null_ptr, 0, Field::NONE,
			    name, table, 0, unsigned_flag);
3834
  case MYSQL_TYPE_NEWDATE:
3835 3836 3837 3838 3839 3840 3841 3842
  case MYSQL_TYPE_DATE:
    return new Field_date(maybe_null, name, table, &my_charset_bin);
  case MYSQL_TYPE_TIME:
    return new Field_time(maybe_null, name, table, &my_charset_bin);
  case MYSQL_TYPE_TIMESTAMP:
  case MYSQL_TYPE_DATETIME:
    return new Field_datetime(maybe_null, name, table, &my_charset_bin);
  case MYSQL_TYPE_YEAR:
3843 3844
    return new Field_year((char*) 0, max_length, null_ptr, 0, Field::NONE,
			  name, table);
unknown's avatar
unknown committed
3845 3846 3847
  case MYSQL_TYPE_BIT:
    return new Field_bit_as_char(NULL, max_length, null_ptr, 0, NULL, 0,
                                 Field::NONE, name, table);
3848
  default:
3849
    /* This case should never be chosen */
3850 3851
    DBUG_ASSERT(0);
    /* If something goes awfully wrong, it's better to get a string than die */
3852 3853
  case MYSQL_TYPE_ENUM:
  case MYSQL_TYPE_SET:
3854
  case MYSQL_TYPE_STRING:
3855
  case MYSQL_TYPE_VAR_STRING:
3856
  case MYSQL_TYPE_VARCHAR:
3857
    return make_string_field(table);
3858 3859 3860 3861 3862
  case MYSQL_TYPE_TINY_BLOB:
  case MYSQL_TYPE_MEDIUM_BLOB:
  case MYSQL_TYPE_LONG_BLOB:
  case MYSQL_TYPE_BLOB:
  case MYSQL_TYPE_GEOMETRY:
3863 3864
    return new Field_blob(max_length, maybe_null, name, table,
                          collation.collation);
3865
    break;					// Blob handled outside of case
3866 3867 3868
  }
}

3869

3870 3871
/* ARGSUSED */
void Item_field::make_field(Send_field *tmp_field)
unknown's avatar
unknown committed
3872
{
3873
  field->make_field(tmp_field);
3874
  DBUG_ASSERT(tmp_field->table_name != 0);
3875 3876
  if (name)
    tmp_field->col_name=name;			// Use user supplied name
unknown's avatar
unknown committed
3877 3878
}

3879

unknown's avatar
unknown committed
3880
/*
3881
  Set a field:s value from a item
unknown's avatar
unknown committed
3882 3883 3884 3885 3886 3887 3888
*/

void Item_field::save_org_in_field(Field *to)
{
  if (field->is_null())
  {
    null_value=1;
3889
    set_field_to_null_with_conversions(to, 1);
unknown's avatar
unknown committed
3890 3891 3892 3893 3894 3895 3896 3897 3898
  }
  else
  {
    to->set_notnull();
    field_conv(to,field);
    null_value=0;
  }
}

unknown's avatar
unknown committed
3899
int Item_field::save_in_field(Field *to, bool no_conversions)
unknown's avatar
unknown committed
3900 3901 3902 3903
{
  if (result_field->is_null())
  {
    null_value=1;
3904
    return set_field_to_null_with_conversions(to, no_conversions);
unknown's avatar
unknown committed
3905 3906 3907 3908 3909 3910 3911 3912 3913 3914
  }
  else
  {
    to->set_notnull();
    field_conv(to,result_field);
    null_value=0;
  }
  return 0;
}

3915

unknown's avatar
unknown committed
3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931
/*
  Store null in field

  SYNOPSIS
    save_in_field()
    field		Field where we want to store NULL

  DESCRIPTION
    This is used on INSERT.
    Allow NULL to be inserted in timestamp and auto_increment values

  RETURN VALUES
    0	 ok
    1	 Field doesn't support NULL values and can't handle 'field = NULL'
*/   

unknown's avatar
unknown committed
3932
int Item_null::save_in_field(Field *field, bool no_conversions)
unknown's avatar
unknown committed
3933
{
3934
  return set_field_to_null_with_conversions(field, no_conversions);
unknown's avatar
unknown committed
3935 3936 3937
}


3938 3939 3940 3941 3942 3943 3944 3945
/*
  Store null in field

  SYNOPSIS
    save_safe_in_field()
    field		Field where we want to store NULL

  RETURN VALUES
unknown's avatar
unknown committed
3946
    0	 OK
3947 3948 3949
    1	 Field doesn't support NULL values
*/   

unknown's avatar
unknown committed
3950
int Item_null::save_safe_in_field(Field *field)
unknown's avatar
unknown committed
3951 3952 3953 3954 3955
{
  return set_field_to_null(field);
}


unknown's avatar
unknown committed
3956
int Item::save_in_field(Field *field, bool no_conversions)
unknown's avatar
unknown committed
3957
{
3958
  int error;
unknown's avatar
unknown committed
3959 3960 3961 3962 3963
  if (result_type() == STRING_RESULT ||
      result_type() == REAL_RESULT &&
      field->result_type() == STRING_RESULT)
  {
    String *result;
3964
    CHARSET_INFO *cs= collation.collation;
unknown's avatar
unknown committed
3965
    char buff[MAX_FIELD_WIDTH];		// Alloc buffer for small columns
unknown's avatar
unknown committed
3966
    str_value.set_quick(buff, sizeof(buff), cs);
unknown's avatar
unknown committed
3967 3968
    result=val_str(&str_value);
    if (null_value)
3969
    {
unknown's avatar
unknown committed
3970
      str_value.set_quick(0, 0, cs);
3971
      return set_field_to_null_with_conversions(field, no_conversions);
3972
    }
3973 3974 3975

    /* NOTE: If null_value == FALSE, "result" must be not NULL.  */

unknown's avatar
unknown committed
3976
    field->set_notnull();
3977
    error=field->store(result->ptr(),result->length(),cs);
3978
    str_value.set_quick(0, 0, cs);
unknown's avatar
unknown committed
3979 3980 3981
  }
  else if (result_type() == REAL_RESULT)
  {
3982
    double nr= val_real();
unknown's avatar
unknown committed
3983 3984 3985
    if (null_value)
      return set_field_to_null(field);
    field->set_notnull();
3986
    error=field->store(nr);
unknown's avatar
unknown committed
3987
  }
unknown's avatar
unknown committed
3988 3989 3990 3991 3992 3993 3994 3995 3996
  else if (result_type() == DECIMAL_RESULT)
  {
    my_decimal decimal_value;
    my_decimal *value= val_decimal(&decimal_value);
    if (null_value)
      return set_field_to_null(field);
    field->set_notnull();
    error=field->store_decimal(value);
  }
unknown's avatar
unknown committed
3997 3998 3999 4000
  else
  {
    longlong nr=val_int();
    if (null_value)
4001
      return set_field_to_null_with_conversions(field, no_conversions);
unknown's avatar
unknown committed
4002
    field->set_notnull();
4003
    error=field->store(nr, unsigned_flag);
unknown's avatar
unknown committed
4004
  }
unknown's avatar
unknown committed
4005
  return error;
unknown's avatar
unknown committed
4006 4007
}

4008

unknown's avatar
unknown committed
4009
int Item_string::save_in_field(Field *field, bool no_conversions)
unknown's avatar
unknown committed
4010 4011 4012 4013 4014 4015
{
  String *result;
  result=val_str(&str_value);
  if (null_value)
    return set_field_to_null(field);
  field->set_notnull();
unknown's avatar
unknown committed
4016
  return field->store(result->ptr(),result->length(),collation.collation);
unknown's avatar
unknown committed
4017 4018
}

4019

unknown's avatar
unknown committed
4020
int Item_uint::save_in_field(Field *field, bool no_conversions)
4021
{
4022
  /* Item_int::save_in_field handles both signed and unsigned. */
unknown's avatar
unknown committed
4023
  return Item_int::save_in_field(field, no_conversions);
4024 4025
}

unknown's avatar
unknown committed
4026 4027

int Item_int::save_in_field(Field *field, bool no_conversions)
unknown's avatar
unknown committed
4028 4029 4030 4031 4032
{
  longlong nr=val_int();
  if (null_value)
    return set_field_to_null(field);
  field->set_notnull();
4033
  return field->store(nr, unsigned_flag);
unknown's avatar
unknown committed
4034 4035
}

unknown's avatar
unknown committed
4036 4037 4038 4039 4040 4041 4042 4043

int Item_decimal::save_in_field(Field *field, bool no_conversions)
{
  field->set_notnull();
  return field->store_decimal(&decimal_value);
}


4044 4045 4046 4047 4048 4049 4050 4051 4052 4053 4054 4055 4056 4057 4058 4059
bool Item_int::eq(const Item *arg, bool binary_cmp) const
{
  /* No need to check for null value as basic constant can't be NULL */
  if (arg->basic_const_item() && arg->type() == type())
  {
    /*
      We need to cast off const to call val_int(). This should be OK for
      a basic constant.
    */
    Item *item= (Item*) arg;
    return item->val_int() == value && item->unsigned_flag == unsigned_flag;
  }
  return FALSE;
}


4060 4061
Item *Item_int_with_ref::new_item()
{
4062
  DBUG_ASSERT(ref->const_item());
4063 4064 4065 4066 4067 4068 4069 4070 4071 4072
  /*
    We need to evaluate the constant to make sure it works with
    parameter markers.
  */
  return (ref->unsigned_flag ?
          new Item_uint(ref->name, ref->val_int(), ref->max_length) :
          new Item_int(ref->name, ref->val_int(), ref->max_length));
}


unknown's avatar
unknown committed
4073 4074
Item_num *Item_uint::neg()
{
4075
  Item_decimal *item= new Item_decimal(value, 1);
unknown's avatar
unknown committed
4076
  return item->neg();
unknown's avatar
unknown committed
4077
}
unknown's avatar
unknown committed
4078

unknown's avatar
unknown committed
4079

4080 4081 4082 4083 4084 4085 4086 4087 4088 4089 4090 4091 4092 4093 4094 4095 4096 4097 4098 4099 4100 4101 4102
static uint nr_of_decimals(const char *str, const char *end)
{
  const char *decimal_point;

  /* Find position for '.' */
  for (;;)
  {
    if (str == end)
      return 0;
    if (*str == 'e' || *str == 'E')
      return NOT_FIXED_DEC;    
    if (*str++ == '.')
      break;
  }
  decimal_point= str;
  for (; my_isdigit(system_charset_info, *str) ; str++)
    ;
  if (*str == 'e' || *str == 'E')
    return NOT_FIXED_DEC;
  return (uint) (str - decimal_point);
}


unknown's avatar
unknown committed
4103 4104 4105 4106 4107
/*
  This function is only called during parsing. We will signal an error if
  value is not a true double value (overflow)
*/

unknown's avatar
unknown committed
4108
Item_float::Item_float(const char *str_arg, uint length)
unknown's avatar
unknown committed
4109 4110
{
  int error;
4111 4112 4113
  char *end_not_used;
  value= my_strntod(&my_charset_bin, (char*) str_arg, length, &end_not_used,
                    &error);
unknown's avatar
unknown committed
4114 4115 4116 4117 4118 4119 4120
  if (error)
  {
    /*
      Note that we depend on that str_arg is null terminated, which is true
      when we are in the parser
    */
    DBUG_ASSERT(str_arg[length] == 0);
4121
    my_error(ER_ILLEGAL_VALUE_FOR_TYPE, MYF(0), "double", (char*) str_arg);
unknown's avatar
unknown committed
4122 4123
  }
  presentation= name=(char*) str_arg;
4124
  decimals=(uint8) nr_of_decimals(str_arg, str_arg+length);
unknown's avatar
unknown committed
4125 4126 4127 4128 4129
  max_length=length;
  fixed= 1;
}


unknown's avatar
unknown committed
4130
int Item_float::save_in_field(Field *field, bool no_conversions)
unknown's avatar
unknown committed
4131
{
4132
  double nr= val_real();
unknown's avatar
unknown committed
4133 4134 4135
  if (null_value)
    return set_field_to_null(field);
  field->set_notnull();
unknown's avatar
unknown committed
4136
  return field->store(nr);
unknown's avatar
unknown committed
4137 4138
}

4139

unknown's avatar
unknown committed
4140
void Item_float::print(String *str)
4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153
{
  if (presentation)
  {
    str->append(presentation);
    return;
  }
  char buffer[20];
  String num(buffer, sizeof(buffer), &my_charset_bin);
  num.set(value, decimals, &my_charset_bin);
  str->append(num);
}


unknown's avatar
unknown committed
4154 4155 4156 4157 4158
/*
  hex item
  In string context this is a binary string.
  In number context this is a longlong value.
*/
unknown's avatar
unknown committed
4159

4160
bool Item_float::eq(const Item *arg, bool binary_cmp) const
4161 4162 4163 4164 4165 4166 4167 4168
{
  if (arg->basic_const_item() && arg->type() == type())
  {
    /*
      We need to cast off const to call val_int(). This should be OK for
      a basic constant.
    */
    Item *item= (Item*) arg;
4169
    return item->val_real() == value;
4170 4171 4172 4173
  }
  return FALSE;
}

unknown's avatar
unknown committed
4174

unknown's avatar
unknown committed
4175
inline uint char_val(char X)
unknown's avatar
unknown committed
4176 4177 4178 4179 4180 4181
{
  return (uint) (X >= '0' && X <= '9' ? X-'0' :
		 X >= 'A' && X <= 'Z' ? X-'A'+10 :
		 X-'a'+10);
}

4182

unknown's avatar
unknown committed
4183
Item_hex_string::Item_hex_string(const char *str, uint str_length)
unknown's avatar
unknown committed
4184 4185 4186 4187 4188 4189
{
  name=(char*) str-2;				// Lex makes this start with 0x
  max_length=(str_length+1)/2;
  char *ptr=(char*) sql_alloc(max_length+1);
  if (!ptr)
    return;
unknown's avatar
unknown committed
4190
  str_value.set(ptr,max_length,&my_charset_bin);
unknown's avatar
unknown committed
4191 4192 4193 4194 4195 4196 4197 4198 4199
  char *end=ptr+max_length;
  if (max_length*2 != str_length)
    *ptr++=char_val(*str++);			// Not even, assume 0 prefix
  while (ptr != end)
  {
    *ptr++= (char) (char_val(str[0])*16+char_val(str[1]));
    str+=2;
  }
  *ptr=0;					// Keep purify happy
4200
  collation.set(&my_charset_bin, DERIVATION_COERCIBLE);
unknown's avatar
unknown committed
4201
  fixed= 1;
unknown's avatar
unknown committed
4202
  unsigned_flag= 1;
unknown's avatar
unknown committed
4203 4204
}

unknown's avatar
unknown committed
4205
longlong Item_hex_string::val_int()
unknown's avatar
unknown committed
4206
{
unknown's avatar
unknown committed
4207
  // following assert is redundant, because fixed=1 assigned in constructor
4208
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
4209 4210 4211 4212 4213 4214 4215 4216 4217 4218
  char *end=(char*) str_value.ptr()+str_value.length(),
       *ptr=end-min(str_value.length(),sizeof(longlong));

  ulonglong value=0;
  for (; ptr != end ; ptr++)
    value=(value << 8)+ (ulonglong) (uchar) *ptr;
  return (longlong) value;
}


unknown's avatar
unknown committed
4219 4220 4221 4222 4223 4224 4225 4226 4227 4228
my_decimal *Item_hex_string::val_decimal(my_decimal *decimal_value)
{
  // following assert is redundant, because fixed=1 assigned in constructor
  DBUG_ASSERT(fixed == 1);
  ulonglong value= (ulonglong)val_int();
  int2my_decimal(E_DEC_FATAL_ERROR, value, TRUE, decimal_value);
  return (decimal_value);
}


unknown's avatar
unknown committed
4229
int Item_hex_string::save_in_field(Field *field, bool no_conversions)
unknown's avatar
unknown committed
4230
{
4231
  int error;
unknown's avatar
unknown committed
4232 4233 4234
  field->set_notnull();
  if (field->result_type() == STRING_RESULT)
  {
4235
    error=field->store(str_value.ptr(),str_value.length(),collation.collation);
unknown's avatar
unknown committed
4236 4237 4238 4239
  }
  else
  {
    longlong nr=val_int();
4240
    error=field->store(nr, TRUE);    // Assume hex numbers are unsigned
unknown's avatar
unknown committed
4241
  }
unknown's avatar
unknown committed
4242
  return error;
unknown's avatar
unknown committed
4243 4244 4245
}


4246
bool Item_hex_string::eq(const Item *arg, bool binary_cmp) const
4247 4248 4249 4250 4251 4252 4253 4254 4255 4256
{
  if (arg->basic_const_item() && arg->type() == type())
  {
    if (binary_cmp)
      return !stringcmp(&str_value, &arg->str_value);
    return !sortcmp(&str_value, &arg->str_value, collation.collation);
  }
  return FALSE;
}

unknown's avatar
unknown committed
4257

unknown's avatar
unknown committed
4258
Item *Item_hex_string::safe_charset_converter(CHARSET_INFO *tocs)
unknown's avatar
unknown committed
4259 4260 4261 4262 4263 4264 4265
{
  Item_string *conv;
  String tmp, *str= val_str(&tmp);

  if (!(conv= new Item_string(str->ptr(), str->length(), tocs)))
    return NULL;
  conv->str_value.copy();
4266
  conv->str_value.mark_as_const();
unknown's avatar
unknown committed
4267 4268 4269 4270
  return conv;
}


unknown's avatar
unknown committed
4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307 4308
/*
  bin item.
  In string context this is a binary string.
  In number context this is a longlong value.
*/
  
Item_bin_string::Item_bin_string(const char *str, uint str_length)
{
  const char *end= str + str_length - 1;
  uchar bits= 0;
  uint power= 1;

  name= (char*) str - 2;
  max_length= (str_length + 7) >> 3;
  char *ptr= (char*) sql_alloc(max_length + 1);
  if (!ptr)
    return;
  str_value.set(ptr, max_length, &my_charset_bin);
  ptr+= max_length - 1;
  ptr[1]= 0;                     // Set end null for string
  for (; end >= str; end--)
  {
    if (power == 256)
    {
      power= 1;
      *ptr--= bits;
      bits= 0;     
    }
    if (*end == '1')
      bits|= power; 
    power<<= 1;
  }
  *ptr= (char) bits;
  collation.set(&my_charset_bin, DERIVATION_COERCIBLE);
  fixed= 1;
}


4309 4310 4311 4312 4313
/*
  Pack data in buffer for sending
*/

bool Item_null::send(Protocol *protocol, String *packet)
unknown's avatar
unknown committed
4314
{
4315
  return protocol->store_null();
unknown's avatar
unknown committed
4316 4317 4318
}

/*
4319
  This is only called from items that is not of type item_field
unknown's avatar
unknown committed
4320 4321
*/

4322
bool Item::send(Protocol *protocol, String *buffer)
unknown's avatar
unknown committed
4323
{
4324 4325
  bool result;
  enum_field_types type;
4326
  LINT_INIT(result);                     // Will be set if null_value == 0
4327 4328 4329

  switch ((type=field_type())) {
  default:
4330 4331 4332 4333 4334 4335 4336 4337 4338
  case MYSQL_TYPE_NULL:
  case MYSQL_TYPE_DECIMAL:
  case MYSQL_TYPE_ENUM:
  case MYSQL_TYPE_SET:
  case MYSQL_TYPE_TINY_BLOB:
  case MYSQL_TYPE_MEDIUM_BLOB:
  case MYSQL_TYPE_LONG_BLOB:
  case MYSQL_TYPE_BLOB:
  case MYSQL_TYPE_GEOMETRY:
4339 4340
  case MYSQL_TYPE_STRING:
  case MYSQL_TYPE_VAR_STRING:
4341
  case MYSQL_TYPE_VARCHAR:
unknown's avatar
unknown committed
4342
  case MYSQL_TYPE_BIT:
unknown's avatar
unknown committed
4343
  case MYSQL_TYPE_NEWDECIMAL:
4344 4345 4346
  {
    String *res;
    if ((res=val_str(buffer)))
4347
      result= protocol->store(res->ptr(),res->length(),res->charset());
4348 4349 4350 4351 4352 4353 4354 4355 4356 4357 4358
    break;
  }
  case MYSQL_TYPE_TINY:
  {
    longlong nr;
    nr= val_int();
    if (!null_value)
      result= protocol->store_tiny(nr);
    break;
  }
  case MYSQL_TYPE_SHORT:
unknown's avatar
unknown committed
4359
  case MYSQL_TYPE_YEAR:
4360 4361 4362 4363 4364 4365 4366
  {
    longlong nr;
    nr= val_int();
    if (!null_value)
      result= protocol->store_short(nr);
    break;
  }
4367
  case MYSQL_TYPE_INT24:
4368 4369 4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383
  case MYSQL_TYPE_LONG:
  {
    longlong nr;
    nr= val_int();
    if (!null_value)
      result= protocol->store_long(nr);
    break;
  }
  case MYSQL_TYPE_LONGLONG:
  {
    longlong nr;
    nr= val_int();
    if (!null_value)
      result= protocol->store_longlong(nr, unsigned_flag);
    break;
  }
unknown's avatar
unknown committed
4384 4385 4386
  case MYSQL_TYPE_FLOAT:
  {
    float nr;
4387
    nr= (float) val_real();
unknown's avatar
unknown committed
4388 4389 4390 4391
    if (!null_value)
      result= protocol->store(nr, decimals, buffer);
    break;
  }
4392 4393
  case MYSQL_TYPE_DOUBLE:
  {
4394
    double nr= val_real();
4395 4396 4397 4398 4399 4400
    if (!null_value)
      result= protocol->store(nr, decimals, buffer);
    break;
  }
  case MYSQL_TYPE_DATETIME:
  case MYSQL_TYPE_DATE:
4401
  case MYSQL_TYPE_TIMESTAMP:
4402 4403
  {
    TIME tm;
4404
    get_date(&tm, TIME_FUZZY_DATE);
4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425
    if (!null_value)
    {
      if (type == MYSQL_TYPE_DATE)
	return protocol->store_date(&tm);
      else
	result= protocol->store(&tm);
    }
    break;
  }
  case MYSQL_TYPE_TIME:
  {
    TIME tm;
    get_time(&tm);
    if (!null_value)
      result= protocol->store_time(&tm);
    break;
  }
  }
  if (null_value)
    result= protocol->store_null();
  return result;
unknown's avatar
unknown committed
4426 4427
}

4428 4429

bool Item_field::send(Protocol *protocol, String *buffer)
unknown's avatar
unknown committed
4430
{
4431
  return protocol->store(result_field);
unknown's avatar
unknown committed
4432 4433
}

4434

4435 4436 4437 4438 4439
Item_ref::Item_ref(Name_resolution_context *context_arg,
                   Item **item, const char *table_name_arg,
                   const char *field_name_arg)
  :Item_ident(context_arg, NullS, table_name_arg, field_name_arg),
   result_field(0), ref(item)
unknown's avatar
unknown committed
4440 4441 4442 4443
{
  /*
    This constructor used to create some internals references over fixed items
  */
4444
  DBUG_ASSERT(ref != 0);
4445
  if (*ref && (*ref)->fixed)
unknown's avatar
unknown committed
4446 4447 4448 4449
    set_properties();
}


4450
/*
4451
  Resolve the name of a reference to a column reference.
4452 4453 4454

  SYNOPSIS
    Item_ref::fix_fields()
4455 4456
    thd       [in]      current thread
    reference [in/out]  view column if this item was resolved to a view column
4457 4458

  DESCRIPTION
4459 4460
    The method resolves the column reference represented by 'this' as a column
    present in one of: GROUP BY clause, SELECT clause, outer queries. It is
4461 4462
    used typically for columns in the HAVING clause which are not under
    aggregate functions.
4463 4464

  NOTES
4465 4466
    The name resolution algorithm used is (where [T_j] is an optional table
    name that qualifies the column name):
4467

4468 4469 4470
      resolve_extended([T_j].col_ref_i)
      {
        Search for a column or derived column named col_ref_i [in table T_j]
4471
        in the SELECT and GROUP clauses of Q.
4472

4473 4474
        if such a column is NOT found AND    // Lookup in outer queries.
           there are outer queries
4475 4476 4477
        {
          for each outer query Q_k beginning from the inner-most one
         {
4478 4479 4480 4481 4482 4483 4484 4485
            Search for a column or derived column named col_ref_i
            [in table T_j] in the SELECT and GROUP clauses of Q_k.

            if such a column is not found AND
               - Q_k is not a group query AND
               - Q_k is not inside an aggregate function
               OR
               - Q_(k-1) is not in a HAVING or SELECT clause of Q_k
4486 4487 4488 4489 4490 4491 4492
            {
              search for a column or derived column named col_ref_i
              [in table T_j] in the FROM clause of Q_k;
            }
          }
        }
      }
4493 4494

    This procedure treats GROUP BY and SELECT clauses as one namespace for
4495 4496 4497
    column references in HAVING. Notice that compared to
    Item_field::fix_fields, here we first search the SELECT and GROUP BY
    clauses, and then we search the FROM clause.
4498

4499 4500 4501
  POSTCONDITION
    Item_ref::ref is 0 or points to a valid item

4502 4503 4504 4505
  RETURN
    TRUE  if error
    FALSE on success
*/
unknown's avatar
unknown committed
4506

4507
bool Item_ref::fix_fields(THD *thd, Item **reference)
unknown's avatar
unknown committed
4508
{
4509
  enum_parsing_place place= NO_MATTER;
4510
  DBUG_ASSERT(fixed == 0);
4511 4512
  SELECT_LEX *current_sel= thd->lex->current_select;

unknown's avatar
unknown committed
4513
  if (!ref || ref == not_found_item)
unknown's avatar
unknown committed
4514
  {
4515 4516 4517
    if (!(ref= resolve_ref_in_select_and_group(thd, this,
                                               context->select_lex)))
      goto error;             /* Some error occurred (e.g. ambiguous names). */
4518

4519
    if (ref == not_found_item) /* This reference was not resolved. */
unknown's avatar
unknown committed
4520
    {
4521 4522
      Name_resolution_context *last_checked_context= context;
      Name_resolution_context *outer_context= context->outer_context;
4523 4524 4525
      Field *from_field;
      ref= 0;

4526
      if (!outer_context)
4527 4528 4529 4530
      {
        /* The current reference cannot be resolved in this query. */
        my_error(ER_BAD_FIELD_ERROR,MYF(0),
                 this->full_name(), current_thd->where);
4531
        goto error;
4532
      }
4533

unknown's avatar
unknown committed
4534
      /*
4535 4536 4537
        If there is an outer context (select), and it is not a derived table
        (which do not support the use of outer fields for now), try to
        resolve this reference in the outer select(s).
4538

4539 4540 4541
        We treat each subselect as a separate namespace, so that different
        subselects may contain columns with the same names. The subselects are
        searched starting from the innermost.
unknown's avatar
unknown committed
4542
      */
4543 4544
      from_field= (Field*) not_found_field;

4545
      do
4546
      {
4547 4548 4549 4550
        SELECT_LEX *select= outer_context->select_lex;
        Item_subselect *prev_subselect_item=
          last_checked_context->select_lex->master_unit()->item;
        last_checked_context= outer_context;
4551

4552
        /* Search in the SELECT and GROUP lists of the outer select. */
4553
        if (outer_context->resolve_in_select_list)
4554
        {
4555 4556
          if (!(ref= resolve_ref_in_select_and_group(thd, this, select)))
            goto error; /* Some error occurred (e.g. ambiguous names). */
4557
          if (ref != not_found_item)
4558
          {
4559 4560 4561 4562
            DBUG_ASSERT(*ref && (*ref)->fixed);
            prev_subselect_item->used_tables_cache|= (*ref)->used_tables();
            prev_subselect_item->const_item_cache&= (*ref)->const_item();
            break;
4563 4564
          }
          /*
4565 4566 4567
            Set ref to 0 to ensure that we get an error in case we replaced
            this item with another item and still use this item in some
            other place of the parse tree.
4568
          */
4569
          ref= 0;
4570
        }
4571

4572 4573 4574 4575 4576
        place= prev_subselect_item->parsing_place;
        /*
          Check table fields only if the subquery is used somewhere out of
          HAVING or the outer SELECT does not use grouping (i.e. tables are
          accessible).
4577
          TODO:
4578 4579 4580 4581 4582 4583
          Here we could first find the field anyway, and then test this
          condition, so that we can give a better error message -
          ER_WRONG_FIELD_WITH_GROUP, instead of the less informative
          ER_BAD_FIELD_ERROR which we produce now.
        */
        if ((place != IN_HAVING ||
4584 4585
             (!select->with_sum_func &&
              select->group_list.elements == 0)))
4586
        {
4587
          /*
4588 4589 4590
            In case of view, find_field_in_tables() write pointer to view
            field expression to 'reference', i.e. it substitute that
            expression instead of this Item_ref
4591
          */
4592
          from_field= find_field_in_tables(thd, this,
unknown's avatar
unknown committed
4593 4594 4595 4596
                                           outer_context->
                                             first_name_resolution_table,
                                           outer_context->
                                             last_name_resolution_table,
4597 4598
                                           reference,
                                           IGNORE_EXCEPT_NON_UNIQUE,
4599
                                           TRUE, TRUE);
4600
          if (! from_field)
4601
            goto error;
4602
          if (from_field == view_ref_found)
4603
          {
4604 4605 4606 4607 4608 4609
            Item::Type type= (*reference)->type();
            prev_subselect_item->used_tables_cache|=
              (*reference)->used_tables();
            prev_subselect_item->const_item_cache&=
              (*reference)->const_item();
            DBUG_ASSERT((*reference)->type() == REF_ITEM);
4610 4611
            mark_as_dependent(thd, last_checked_context->select_lex,
                              context->select_lex, this,
4612 4613 4614 4615 4616 4617 4618
                              ((type == REF_ITEM || type == FIELD_ITEM) ?
                               (Item_ident*) (*reference) :
                               0));
            /*
              view reference found, we substituted it instead of this
              Item, so can quit
            */
4619 4620
            return FALSE;
          }
4621 4622 4623 4624 4625 4626
          if (from_field != not_found_field)
          {
            prev_subselect_item->used_tables_cache|= from_field->table->map;
            prev_subselect_item->const_item_cache= 0;
            break;
          }
4627
        }
4628 4629 4630 4631 4632 4633
        DBUG_ASSERT(from_field == not_found_field);

        /* Reference is not found => depend on outer (or just error). */
        prev_subselect_item->used_tables_cache|= OUTER_REF_TABLE_BIT;
        prev_subselect_item->const_item_cache= 0;

4634 4635
        outer_context= outer_context->outer_context;
      } while (outer_context);
4636 4637 4638

      DBUG_ASSERT(from_field != 0 && from_field != view_ref_found);
      if (from_field != not_found_field)
4639
      {
4640 4641
        Item_field* fld;
        if (!(fld= new Item_field(from_field)))
4642
          goto error;
4643
        thd->change_item_tree(reference, fld);
4644 4645
        mark_as_dependent(thd, last_checked_context->select_lex,
                          thd->lex->current_select, this, fld);
4646 4647 4648 4649 4650 4651
        return FALSE;
      }
      if (ref == 0)
      {
        /* The item was not a table field and not a reference */
        my_error(ER_BAD_FIELD_ERROR, MYF(0),
4652
                 this->full_name(), current_thd->where);
4653
        goto error;
4654
      }
4655 4656
      /* Should be checked in resolve_ref_in_select_and_group(). */
      DBUG_ASSERT(*ref && (*ref)->fixed);
4657 4658
      mark_as_dependent(thd, last_checked_context->select_lex,
                        context->select_lex, this, this);
4659
    }
unknown's avatar
unknown committed
4660
  }
4661

4662
  DBUG_ASSERT(*ref);
4663
  /*
4664 4665 4666
    Check if this is an incorrect reference in a group function or forward
    reference. Do not issue an error if this is an unnamed reference inside an
    aggregate function.
4667
  */
4668
  if (((*ref)->with_sum_func && name &&
unknown's avatar
unknown committed
4669 4670
       !(current_sel->linkage != GLOBAL_OPTIONS_TYPE &&
         current_sel->having_fix_field)) ||
4671 4672
      !(*ref)->fixed)
  {
4673 4674 4675 4676
    my_error(ER_ILLEGAL_REFERENCE, MYF(0),
             name, ((*ref)->with_sum_func?
                    "reference to group function":
                    "forward reference in item list"));
4677
    goto error;
4678
  }
4679 4680 4681

  set_properties();

4682
  if ((*ref)->check_cols(1))
4683
    goto error;
4684
  return FALSE;
4685 4686 4687 4688

error:
  context->process_error(thd);
  return TRUE;
4689 4690
}

4691

4692 4693
void Item_ref::set_properties()
{
4694 4695 4696
  max_length= (*ref)->max_length;
  maybe_null= (*ref)->maybe_null;
  decimals=   (*ref)->decimals;
4697
  collation.set((*ref)->collation);
unknown's avatar
unknown committed
4698 4699 4700 4701
  /*
    We have to remember if we refer to a sum function, to ensure that
    split_sum_func() doesn't try to change the reference.
  */
unknown's avatar
unknown committed
4702
  with_sum_func= (*ref)->with_sum_func;
unknown's avatar
Merge  
unknown committed
4703
  unsigned_flag= (*ref)->unsigned_flag;
unknown's avatar
unknown committed
4704 4705 4706 4707
  if ((*ref)->type() == FIELD_ITEM)
    alias_name_used= ((Item_ident *) (*ref))->alias_name_used;
  else
    alias_name_used= TRUE; // it is not field, so it is was resolved by alias
4708
  fixed= 1;
unknown's avatar
unknown committed
4709 4710
}

4711

unknown's avatar
unknown committed
4712 4713
void Item_ref::cleanup()
{
unknown's avatar
unknown committed
4714
  DBUG_ENTER("Item_ref::cleanup");
unknown's avatar
unknown committed
4715
  Item_ident::cleanup();
4716
  result_field= 0;
unknown's avatar
unknown committed
4717
  DBUG_VOID_RETURN;
unknown's avatar
unknown committed
4718 4719 4720
}


unknown's avatar
unknown committed
4721 4722
void Item_ref::print(String *str)
{
4723
  if (ref)
unknown's avatar
unknown committed
4724 4725 4726 4727 4728 4729
    (*ref)->print(str);
  else
    Item_ident::print(str);
}


4730 4731 4732 4733 4734 4735 4736 4737
bool Item_ref::send(Protocol *prot, String *tmp)
{
  if (result_field)
    return prot->store(result_field);
  return (*ref)->send(prot, tmp);
}


4738 4739 4740 4741 4742 4743 4744 4745
double Item_ref::val_result()
{
  if (result_field)
  {
    if ((null_value= result_field->is_null()))
      return 0.0;
    return result_field->val_real();
  }
4746
  return val_real();
4747 4748 4749 4750 4751 4752 4753 4754
}


longlong Item_ref::val_int_result()
{
  if (result_field)
  {
    if ((null_value= result_field->is_null()))
4755
      return 0;
4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774
    return result_field->val_int();
  }
  return val_int();
}


String *Item_ref::str_result(String* str)
{
  if (result_field)
  {
    if ((null_value= result_field->is_null()))
      return 0;
    str->set_charset(str_value.charset());
    return result_field->val_str(str, &str_value);
  }
  return val_str(str);
}


unknown's avatar
unknown committed
4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792
my_decimal *Item_ref::val_decimal_result(my_decimal *decimal_value)
{
  if (result_field)
  {
    if ((null_value= result_field->is_null()))
      return 0;
    return result_field->val_decimal(decimal_value);
  }
  return val_decimal(decimal_value);
}


bool Item_ref::val_bool_result()
{
  if (result_field)
  {
    if ((null_value= result_field->is_null()))
      return 0;
4793
    switch (result_field->result_type()) {
unknown's avatar
unknown committed
4794
    case INT_RESULT:
4795
      return result_field->val_int() != 0;
unknown's avatar
unknown committed
4796
    case DECIMAL_RESULT:
4797 4798 4799 4800 4801 4802 4803
    {
      my_decimal decimal_value;
      my_decimal *val= result_field->val_decimal(&decimal_value);
      if (val)
        return !my_decimal_is_zero(val);
      return 0;
    }
unknown's avatar
unknown committed
4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849 4850 4851 4852 4853 4854
    case REAL_RESULT:
    case STRING_RESULT:
      return result_field->val_real() != 0.0;
    case ROW_RESULT:
    default:
      DBUG_ASSERT(0);
    }
  }
  return val_bool();
}


double Item_ref::val_real()
{
  DBUG_ASSERT(fixed);
  double tmp=(*ref)->val_result();
  null_value=(*ref)->null_value;
  return tmp;
}


longlong Item_ref::val_int()
{
  DBUG_ASSERT(fixed);
  longlong tmp=(*ref)->val_int_result();
  null_value=(*ref)->null_value;
  return tmp;
}


bool Item_ref::val_bool()
{
  DBUG_ASSERT(fixed);
  bool tmp= (*ref)->val_bool_result();
  null_value= (*ref)->null_value;
  return tmp;
}


String *Item_ref::val_str(String* tmp)
{
  DBUG_ASSERT(fixed);
  tmp=(*ref)->str_result(tmp);
  null_value=(*ref)->null_value;
  return tmp;
}


bool Item_ref::is_null()
{
  DBUG_ASSERT(fixed);
4855
  return (*ref)->is_null();
unknown's avatar
unknown committed
4856 4857 4858 4859 4860 4861 4862 4863 4864 4865 4866
}


bool Item_ref::get_date(TIME *ltime,uint fuzzydate)
{
  return (null_value=(*ref)->get_date_result(ltime,fuzzydate));
}


my_decimal *Item_ref::val_decimal(my_decimal *decimal_value)
{
unknown's avatar
unknown committed
4867
  my_decimal *val= (*ref)->val_decimal_result(decimal_value);
unknown's avatar
unknown committed
4868 4869 4870 4871
  null_value= (*ref)->null_value;
  return val;
}

4872 4873 4874
int Item_ref::save_in_field(Field *to, bool no_conversions)
{
  int res;
unknown's avatar
unknown committed
4875 4876
  if (result_field)
  {
4877 4878 4879 4880 4881
    if (result_field->is_null())
    {
      null_value= 1;
      return set_field_to_null_with_conversions(to, no_conversions);
    }
unknown's avatar
unknown committed
4882 4883 4884
    to->set_notnull();
    field_conv(to, result_field);
    null_value= 0;
4885 4886 4887 4888 4889 4890 4891
    return 0;
  }
  res= (*ref)->save_in_field(to, no_conversions);
  null_value= (*ref)->null_value;
  return res;
}

unknown's avatar
unknown committed
4892

4893 4894 4895 4896 4897 4898 4899 4900 4901 4902
void Item_ref::make_field(Send_field *field)
{
  (*ref)->make_field(field);
  /* Non-zero in case of a view */
  if (name)
    field->col_name= name;
  if (table_name)
    field->table_name= table_name;
  if (db_name)
    field->db_name= db_name;
unknown's avatar
unknown committed
4903
}
4904 4905


unknown's avatar
unknown committed
4906 4907
void Item_ref_null_helper::print(String *str)
{
4908
  str->append(STRING_WITH_LEN("<ref_null_helper>("));
4909
  if (ref)
unknown's avatar
unknown committed
4910 4911 4912 4913 4914 4915 4916
    (*ref)->print(str);
  else
    str->append('?');
  str->append(')');
}


unknown's avatar
unknown committed
4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 4957 4958
double Item_direct_ref::val_real()
{
  double tmp=(*ref)->val_real();
  null_value=(*ref)->null_value;
  return tmp;
}


longlong Item_direct_ref::val_int()
{
  longlong tmp=(*ref)->val_int();
  null_value=(*ref)->null_value;
  return tmp;
}


String *Item_direct_ref::val_str(String* tmp)
{
  tmp=(*ref)->val_str(tmp);
  null_value=(*ref)->null_value;
  return tmp;
}


my_decimal *Item_direct_ref::val_decimal(my_decimal *decimal_value)
{
  my_decimal *tmp= (*ref)->val_decimal(decimal_value);
  null_value=(*ref)->null_value;
  return tmp;
}


bool Item_direct_ref::val_bool()
{
  bool tmp= (*ref)->val_bool();
  null_value=(*ref)->null_value;
  return tmp;
}


bool Item_direct_ref::is_null()
{
unknown's avatar
unknown committed
4959
  return (*ref)->is_null();
unknown's avatar
unknown committed
4960 4961 4962 4963 4964 4965 4966 4967 4968
}


bool Item_direct_ref::get_date(TIME *ltime,uint fuzzydate)
{
  return (null_value=(*ref)->get_date(ltime,fuzzydate));
}


4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992
/*
  Prepare referenced view viewld then call usual Item_direct_ref::fix_fields

  SYNOPSIS
    Item_direct_view_ref::fix_fields()
    thd         thread handler
    reference   reference on reference where this item stored

  RETURN
    FALSE   OK
    TRUE    Error
*/

bool Item_direct_view_ref::fix_fields(THD *thd, Item **reference)
{
  /* view fild reference must be defined */
  DBUG_ASSERT(*ref);
  /* (*ref)->check_cols() will be made in Item_direct_ref::fix_fields */
  if (!(*ref)->fixed &&
      ((*ref)->fix_fields(thd, ref)))
    return TRUE;
  return Item_direct_ref::fix_fields(thd, reference);
}

4993
/*
4994
  Compare two view column references for equality.
4995 4996 4997 4998 4999 5000 5001

  SYNOPSIS
    Item_direct_view_ref::eq()
    item        item to compare with
    binary_cmp  make binary comparison

  DESCRIPTION
5002 5003 5004 5005 5006 5007 5008
    A view column reference is considered equal to another column
    reference if the second one is a view column and if both column
    references point to the same field. For views 'same field' means
    the same Item_field object in the view translation table, where
    the view translation table contains all result columns of the
    view. This definition ensures that view columns are resolved
    in the same manner as table columns.
5009 5010 5011 5012 5013 5014 5015 5016 5017

  RETURN
    TRUE    Referenced item is equal to given item
    FALSE   otherwise
*/


bool Item_direct_view_ref::eq(const Item *item, bool binary_cmp) const
{
5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029
  if (item->type() == REF_ITEM)
  {
    Item_ref *item_ref= (Item_ref*) item;
    if (item_ref->ref_type() == VIEW_REF)
    {
      Item *item_ref_ref= *(item_ref->ref);
      DBUG_ASSERT((*ref)->type() == FIELD_ITEM &&
                  (item_ref_ref->type() == FIELD_ITEM));
      return (*ref == item_ref_ref);
    }
  }
  return FALSE;
5030
}
5031

unknown's avatar
unknown committed
5032 5033
void Item_null_helper::print(String *str)
{
5034
  str->append(STRING_WITH_LEN("<null_helper>("));
unknown's avatar
unknown committed
5035 5036 5037 5038 5039
  store->print(str);
  str->append(')');
}


unknown's avatar
SCRUM  
unknown committed
5040 5041
bool Item_default_value::eq(const Item *item, bool binary_cmp) const
{
unknown's avatar
SCRUM  
unknown committed
5042
  return item->type() == DEFAULT_VALUE_ITEM && 
unknown's avatar
SCRUM  
unknown committed
5043 5044 5045
    ((Item_default_value *)item)->arg->eq(arg, binary_cmp);
}

5046

5047
bool Item_default_value::fix_fields(THD *thd, Item **items)
unknown's avatar
SCRUM  
unknown committed
5048
{
5049
  Item *real_arg;
unknown's avatar
unknown committed
5050 5051
  Item_field *field_arg;
  Field *def_field;
5052
  DBUG_ASSERT(fixed == 0);
unknown's avatar
unknown committed
5053

unknown's avatar
SCRUM  
unknown committed
5054
  if (!arg)
5055 5056
  {
    fixed= 1;
unknown's avatar
unknown committed
5057
    return FALSE;
5058
  }
5059 5060 5061
  if (!arg->fixed && arg->fix_fields(thd, &arg))
    goto error;

5062

5063 5064
  real_arg= arg->real_item();
  if (real_arg->type() != FIELD_ITEM)
unknown's avatar
SCRUM  
unknown committed
5065
  {
5066
    my_error(ER_NO_DEFAULT_FOR_FIELD, MYF(0), arg->name);
5067
    goto error;
unknown's avatar
SCRUM  
unknown committed
5068
  }
5069

5070
  field_arg= (Item_field *)real_arg;
unknown's avatar
unknown committed
5071 5072
  if (field_arg->field->flags & NO_DEFAULT_VALUE_FLAG)
  {
5073
    my_error(ER_NO_DEFAULT_FOR_FIELD, MYF(0), field_arg->field->field_name);
5074
    goto error;
unknown's avatar
unknown committed
5075 5076
  }
  if (!(def_field= (Field*) sql_alloc(field_arg->field->size_of())))
5077
    goto error;
unknown's avatar
SCRUM  
unknown committed
5078
  memcpy(def_field, field_arg->field, field_arg->field->size_of());
5079
  def_field->move_field(def_field->table->s->default_values -
unknown's avatar
unknown committed
5080
                        def_field->table->record[0]);
unknown's avatar
SCRUM  
unknown committed
5081
  set_field(def_field);
unknown's avatar
unknown committed
5082
  return FALSE;
5083 5084 5085 5086

error:
  context->process_error(thd);
  return TRUE;
unknown's avatar
SCRUM  
unknown committed
5087 5088
}

5089

unknown's avatar
SCRUM  
unknown committed
5090 5091
void Item_default_value::print(String *str)
{
unknown's avatar
SCRUM  
unknown committed
5092 5093
  if (!arg)
  {
5094
    str->append(STRING_WITH_LEN("default"));
unknown's avatar
SCRUM  
unknown committed
5095
    return;
unknown's avatar
SCRUM  
unknown committed
5096
  }
5097
  str->append(STRING_WITH_LEN("default("));
unknown's avatar
SCRUM  
unknown committed
5098 5099 5100
  arg->print(str);
  str->append(')');
}
5101

5102 5103 5104 5105 5106 5107 5108

int Item_default_value::save_in_field(Field *field_arg, bool no_conversions)
{
  if (!arg)
  {
    if (field_arg->flags & NO_DEFAULT_VALUE_FLAG)
    {
5109 5110
      if (context->error_processor == &view_error_processor)
      {
unknown's avatar
unknown committed
5111
        TABLE_LIST *view= cached_table->top_table();
5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126
        push_warning_printf(field_arg->table->in_use,
                            MYSQL_ERROR::WARN_LEVEL_WARN,
                            ER_NO_DEFAULT_FOR_VIEW_FIELD,
                            ER(ER_NO_DEFAULT_FOR_VIEW_FIELD),
                            view->view_db.str,
                            view->view_name.str);
      }
      else
      {
        push_warning_printf(field_arg->table->in_use,
                            MYSQL_ERROR::WARN_LEVEL_WARN,
                            ER_NO_DEFAULT_FOR_FIELD,
                            ER(ER_NO_DEFAULT_FOR_FIELD),
                            field_arg->field_name);
      }
5127 5128 5129 5130 5131 5132 5133 5134 5135
      return 1;
    }
    field_arg->set_default();
    return 0;
  }
  return Item_field::save_in_field(field_arg, no_conversions);
}


unknown's avatar
unknown committed
5136 5137 5138 5139 5140 5141 5142
bool Item_insert_value::eq(const Item *item, bool binary_cmp) const
{
  return item->type() == INSERT_VALUE_ITEM &&
    ((Item_default_value *)item)->arg->eq(arg, binary_cmp);
}


5143
bool Item_insert_value::fix_fields(THD *thd, Item **items)
unknown's avatar
unknown committed
5144
{
5145
  DBUG_ASSERT(fixed == 0);
5146
  /* We should only check that arg is in first table */
5147
  if (!arg->fixed)
5148
  {
5149 5150 5151 5152
    bool res;
    st_table_list *orig_next_table= context->last_name_resolution_table;
    context->last_name_resolution_table= context->first_name_resolution_table;
    res= arg->fix_fields(thd, &arg);
5153
    context->last_name_resolution_table= orig_next_table;
5154 5155
    if (res)
      return TRUE;
5156
  }
5157

unknown's avatar
unknown committed
5158 5159 5160 5161 5162
  if (arg->type() == REF_ITEM)
  {
    Item_ref *ref= (Item_ref *)arg;
    if (ref->ref[0]->type() != FIELD_ITEM)
    {
5163
      my_error(ER_BAD_FIELD_ERROR, MYF(0), "", "VALUES() function");
unknown's avatar
unknown committed
5164
      return TRUE;
unknown's avatar
unknown committed
5165 5166 5167
    }
    arg= ref->ref[0];
  }
5168 5169 5170 5171 5172 5173
  /*
    According to our SQL grammar, VALUES() function can reference
    only to a column.
  */
  DBUG_ASSERT(arg->type() == FIELD_ITEM);

unknown's avatar
unknown committed
5174
  Item_field *field_arg= (Item_field *)arg;
5175

unknown's avatar
unknown committed
5176 5177 5178 5179
  if (field_arg->field->table->insert_values)
  {
    Field *def_field= (Field*) sql_alloc(field_arg->field->size_of());
    if (!def_field)
unknown's avatar
unknown committed
5180
      return TRUE;
unknown's avatar
unknown committed
5181 5182 5183 5184 5185 5186 5187
    memcpy(def_field, field_arg->field, field_arg->field->size_of());
    def_field->move_field(def_field->table->insert_values -
                          def_field->table->record[0]);
    set_field(def_field);
  }
  else
  {
5188
    Field *tmp_field= field_arg->field;
unknown's avatar
unknown committed
5189
    /* charset doesn't matter here, it's to avoid sigsegv only */
5190 5191
    set_field(new Field_null(0, 0, Field::NONE, tmp_field->field_name,
			     tmp_field->table, &my_charset_bin));
unknown's avatar
unknown committed
5192
  }
unknown's avatar
unknown committed
5193
  return FALSE;
unknown's avatar
unknown committed
5194 5195 5196 5197
}

void Item_insert_value::print(String *str)
{
5198
  str->append(STRING_WITH_LEN("values("));
unknown's avatar
unknown committed
5199 5200 5201 5202
  arg->print(str);
  str->append(')');
}

5203 5204

/*
unknown's avatar
unknown committed
5205 5206
  Find index of Field object which will be appropriate for item
  representing field of row being changed in trigger.
5207 5208 5209 5210 5211 5212 5213 5214

  SYNOPSIS
    setup_field()
      thd   - current thread context
      table - table of trigger (and where we looking for fields)

  NOTE
    This function does almost the same as fix_fields() for Item_field
unknown's avatar
unknown committed
5215 5216 5217 5218 5219 5220 5221 5222
    but is invoked right after trigger definition parsing. Since at
    this stage we can't say exactly what Field object (corresponding
    to TABLE::record[0] or TABLE::record[1]) should be bound to this
    Item, we only find out index of the Field and then select concrete
    Field object in fix_fields() (by that time Table_trigger_list::old_field/
    new_field should point to proper array of Fields).
    It also binds Item_trigger_field to Table_triggers_list object for
    table of trigger which uses this item.
5223
*/
unknown's avatar
unknown committed
5224 5225

void Item_trigger_field::setup_field(THD *thd, TABLE *table)
5226 5227 5228 5229 5230
{
  bool save_set_query_id= thd->set_query_id;

  /* TODO: Think more about consequences of this step. */
  thd->set_query_id= 0;
unknown's avatar
unknown committed
5231 5232 5233 5234
  /*
    Try to find field by its name and if it will be found
    set field_idx properly.
  */
unknown's avatar
unknown committed
5235
  (void)find_field_in_table(thd, table, field_name, (uint) strlen(field_name),
5236
                            0, &field_idx);
5237
  thd->set_query_id= save_set_query_id;
unknown's avatar
unknown committed
5238
  triggers= table->triggers;
5239 5240 5241 5242 5243 5244 5245 5246 5247 5248 5249 5250
}


bool Item_trigger_field::eq(const Item *item, bool binary_cmp) const
{
  return item->type() == TRIGGER_FIELD_ITEM &&
         row_version == ((Item_trigger_field *)item)->row_version &&
         !my_strcasecmp(system_charset_info, field_name,
                        ((Item_trigger_field *)item)->field_name);
}


5251
bool Item_trigger_field::fix_fields(THD *thd, Item **items)
5252 5253 5254 5255 5256 5257 5258 5259
{
  /*
    Since trigger is object tightly associated with TABLE object most
    of its set up can be performed during trigger loading i.e. trigger
    parsing! So we have little to do in fix_fields. :)
    FIXME may be we still should bother about permissions here.
  */
  DBUG_ASSERT(fixed == 0);
5260

unknown's avatar
unknown committed
5261
  if (field_idx != (uint)-1)
5262
  {
unknown's avatar
unknown committed
5263 5264
    field= (row_version == OLD_ROW) ? triggers->old_field[field_idx] :
                                      triggers->new_field[field_idx];
5265 5266 5267 5268 5269 5270 5271 5272
    set_field(field);
    fixed= 1;
    return 0;
  }

  my_error(ER_BAD_FIELD_ERROR, MYF(0), field_name,
           (row_version == NEW_ROW) ? "NEW" : "OLD");
  return 1;
5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289 5290 5291 5292 5293
}


void Item_trigger_field::print(String *str)
{
  str->append((row_version == NEW_ROW) ? "NEW" : "OLD", 3);
  str->append('.');
  str->append(field_name);
}


void Item_trigger_field::cleanup()
{
  /*
    Since special nature of Item_trigger_field we should not do most of
    things from Item_field::cleanup() or Item_ident::cleanup() here.
  */
  Item::cleanup();
}


unknown's avatar
unknown committed
5294
/*
5295 5296
  If item is a const function, calculate it and return a const item
  The original item is freed if not returned
unknown's avatar
unknown committed
5297 5298 5299 5300 5301 5302
*/

Item_result item_cmp_type(Item_result a,Item_result b)
{
  if (a == STRING_RESULT && b == STRING_RESULT)
    return STRING_RESULT;
5303
  if (a == INT_RESULT && b == INT_RESULT)
unknown's avatar
unknown committed
5304
    return INT_RESULT;
unknown's avatar
unknown committed
5305 5306
  else if (a == ROW_RESULT || b == ROW_RESULT)
    return ROW_RESULT;
unknown's avatar
unknown committed
5307 5308 5309
  if ((a == INT_RESULT || a == DECIMAL_RESULT) &&
      (b == INT_RESULT || b == DECIMAL_RESULT))
    return DECIMAL_RESULT;
5310
  return REAL_RESULT;
unknown's avatar
unknown committed
5311 5312 5313
}


5314
void resolve_const_item(THD *thd, Item **ref, Item *comp_item)
unknown's avatar
unknown committed
5315
{
5316
  Item *item= *ref;
5317
  Item *new_item= NULL;
unknown's avatar
unknown committed
5318
  if (item->basic_const_item())
5319
    return;                                     // Can't be better
unknown's avatar
unknown committed
5320 5321 5322 5323
  Item_result res_type=item_cmp_type(comp_item->result_type(),
				     item->result_type());
  char *name=item->name;			// Alloced by sql_alloc

5324
  switch (res_type) {
unknown's avatar
unknown committed
5325
  case STRING_RESULT:
unknown's avatar
unknown committed
5326 5327
  {
    char buff[MAX_FIELD_WIDTH];
unknown's avatar
unknown committed
5328
    String tmp(buff,sizeof(buff),&my_charset_bin),*result;
unknown's avatar
unknown committed
5329 5330
    result=item->val_str(&tmp);
    if (item->null_value)
5331 5332 5333 5334 5335 5336 5337
      new_item= new Item_null(name);
    else
    {
      uint length= result->length();
      char *tmp_str= sql_strmake(result->ptr(), length);
      new_item= new Item_string(name, tmp_str, length, result->charset());
    }
unknown's avatar
unknown committed
5338
    break;
unknown's avatar
unknown committed
5339
  }
unknown's avatar
unknown committed
5340
  case INT_RESULT:
unknown's avatar
unknown committed
5341 5342 5343 5344
  {
    longlong result=item->val_int();
    uint length=item->max_length;
    bool null_value=item->null_value;
5345 5346
    new_item= (null_value ? (Item*) new Item_null(name) :
               (Item*) new Item_int(name, result, length));
unknown's avatar
unknown committed
5347
    break;
unknown's avatar
unknown committed
5348
  }
5349
  case ROW_RESULT:
5350
  if (item->type() == Item::ROW_ITEM && comp_item->type() == Item::ROW_ITEM)
5351
  {
5352 5353 5354 5355 5356 5357 5358 5359
    /*
      Substitute constants only in Item_rows. Don't affect other Items
      with ROW_RESULT (eg Item_singlerow_subselect).

      For such Items more optimal is to detect if it is constant and replace
      it with Item_row. This would optimize queries like this:
      SELECT * FROM t1 WHERE (a,b) = (SELECT a,b FROM t2 LIMIT 1);
    */
unknown's avatar
unknown committed
5360 5361 5362
    Item_row *item_row= (Item_row*) item;
    Item_row *comp_item_row= (Item_row*) comp_item;
    uint col;
5363 5364 5365
    new_item= 0;
    /*
      If item and comp_item are both Item_rows and have same number of cols
unknown's avatar
unknown committed
5366 5367 5368
      then process items in Item_row one by one.
      We can't ignore NULL values here as this item may be used with <=>, in
      which case NULL's are significant.
5369
    */
unknown's avatar
unknown committed
5370 5371 5372 5373 5374
    DBUG_ASSERT(item->result_type() == comp_item->result_type());
    DBUG_ASSERT(item_row->cols() == comp_item_row->cols());
    col= item_row->cols();
    while (col-- > 0)
      resolve_const_item(thd, item_row->addr(col), comp_item_row->el(col));
unknown's avatar
unknown committed
5375
    break;
5376
  }
5377
  /* Fallthrough */
unknown's avatar
unknown committed
5378
  case REAL_RESULT:
unknown's avatar
unknown committed
5379
  {						// It must REAL_RESULT
5380
    double result= item->val_real();
unknown's avatar
unknown committed
5381 5382
    uint length=item->max_length,decimals=item->decimals;
    bool null_value=item->null_value;
5383
    new_item= (null_value ? (Item*) new Item_null(name) : (Item*)
unknown's avatar
unknown committed
5384 5385 5386 5387 5388 5389 5390 5391 5392 5393 5394 5395 5396 5397 5398 5399
               new Item_float(name, result, decimals, length));
    break;
  }
  case DECIMAL_RESULT:
  {
    my_decimal decimal_value;
    my_decimal *result= item->val_decimal(&decimal_value);
    uint length= item->max_length, decimals= item->decimals;
    bool null_value= item->null_value;
    new_item= (null_value ?
               (Item*) new Item_null(name) :
               (Item*) new Item_decimal(name, result, length, decimals));
    break;
  }
  default:
    DBUG_ASSERT(0);
unknown's avatar
unknown committed
5400
  }
5401 5402
  if (new_item)
    thd->change_item_tree(ref, new_item);
unknown's avatar
unknown committed
5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419
}

/*
  Return true if the value stored in the field is equal to the const item
  We need to use this on the range optimizer because in some cases
  we can't store the value in the field without some precision/character loss.
*/

bool field_is_equal_to_item(Field *field,Item *item)
{

  Item_result res_type=item_cmp_type(field->result_type(),
				     item->result_type());
  if (res_type == STRING_RESULT)
  {
    char item_buff[MAX_FIELD_WIDTH];
    char field_buff[MAX_FIELD_WIDTH];
unknown's avatar
unknown committed
5420 5421
    String item_tmp(item_buff,sizeof(item_buff),&my_charset_bin),*item_result;
    String field_tmp(field_buff,sizeof(field_buff),&my_charset_bin);
unknown's avatar
unknown committed
5422 5423 5424
    item_result=item->val_str(&item_tmp);
    if (item->null_value)
      return 1;					// This must be true
5425
    field->val_str(&field_tmp);
unknown's avatar
unknown committed
5426
    return !stringcmp(&field_tmp,item_result);
unknown's avatar
unknown committed
5427 5428 5429
  }
  if (res_type == INT_RESULT)
    return 1;					// Both where of type int
unknown's avatar
unknown committed
5430 5431 5432 5433 5434 5435 5436 5437 5438 5439
  if (res_type == DECIMAL_RESULT)
  {
    my_decimal item_buf, *item_val,
               field_buf, *field_val;
    item_val= item->val_decimal(&item_buf);
    if (item->null_value)
      return 1;					// This must be true
    field_val= field->val_decimal(&field_buf);
    return !my_decimal_cmp(item_val, field_val);
  }
5440
  double result= item->val_real();
unknown's avatar
unknown committed
5441 5442 5443 5444 5445
  if (item->null_value)
    return 1;
  return result == field->val_real();
}

5446 5447
Item_cache* Item_cache::get_cache(Item_result type)
{
5448
  switch (type) {
5449 5450 5451 5452
  case INT_RESULT:
    return new Item_cache_int();
  case REAL_RESULT:
    return new Item_cache_real();
unknown's avatar
unknown committed
5453 5454
  case DECIMAL_RESULT:
    return new Item_cache_decimal();
5455 5456
  case STRING_RESULT:
    return new Item_cache_str();
unknown's avatar
unknown committed
5457 5458
  case ROW_RESULT:
    return new Item_cache_row();
5459 5460 5461 5462 5463 5464 5465
  default:
    // should never be in real life
    DBUG_ASSERT(0);
    return 0;
  }
}

unknown's avatar
unknown committed
5466 5467 5468

void Item_cache::print(String *str)
{
5469
  str->append(STRING_WITH_LEN("<cache>("));
unknown's avatar
unknown committed
5470 5471 5472 5473 5474 5475 5476 5477 5478 5479 5480 5481
  if (example)
    example->print(str);
  else
    Item::print(str);
  str->append(')');
}


void Item_cache_int::store(Item *item)
{
  value= item->val_int_result();
  null_value= item->null_value;
unknown's avatar
unknown committed
5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498
  unsigned_flag= item->unsigned_flag;
}


String *Item_cache_int::val_str(String *str)
{
  DBUG_ASSERT(fixed == 1);
  str->set(value, default_charset());
  return str;
}


my_decimal *Item_cache_int::val_decimal(my_decimal *decimal_val)
{
  DBUG_ASSERT(fixed == 1);
  int2my_decimal(E_DEC_FATAL_ERROR, value, unsigned_flag, decimal_val);
  return decimal_val;
unknown's avatar
unknown committed
5499 5500 5501 5502 5503 5504 5505 5506 5507 5508
}


void Item_cache_real::store(Item *item)
{
  value= item->val_result();
  null_value= item->null_value;
}


unknown's avatar
unknown committed
5509 5510 5511
longlong Item_cache_real::val_int()
{
  DBUG_ASSERT(fixed == 1);
5512
  return (longlong) rint(value);
unknown's avatar
unknown committed
5513 5514 5515 5516 5517 5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533 5534
}


String* Item_cache_real::val_str(String *str)
{
  DBUG_ASSERT(fixed == 1);
  str->set(value, decimals, default_charset());
  return str;
}


my_decimal *Item_cache_real::val_decimal(my_decimal *decimal_val)
{
  DBUG_ASSERT(fixed == 1);
  double2my_decimal(E_DEC_FATAL_ERROR, value, decimal_val);
  return decimal_val;
}


void Item_cache_decimal::store(Item *item)
{
  my_decimal *val= item->val_decimal_result(&decimal_value);
5535
  if (!(null_value= item->null_value) && val != &decimal_value)
unknown's avatar
unknown committed
5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570
    my_decimal2decimal(val, &decimal_value);
}

double Item_cache_decimal::val_real()
{
  DBUG_ASSERT(fixed);
  double res;
  my_decimal2double(E_DEC_FATAL_ERROR, &decimal_value, &res);
  return res;
}

longlong Item_cache_decimal::val_int()
{
  DBUG_ASSERT(fixed);
  longlong res;
  my_decimal2int(E_DEC_FATAL_ERROR, &decimal_value, unsigned_flag, &res);
  return res;
}

String* Item_cache_decimal::val_str(String *str)
{
  DBUG_ASSERT(fixed);
  my_decimal_round(E_DEC_FATAL_ERROR, &decimal_value, decimals, FALSE,
                   &decimal_value);
  my_decimal2string(E_DEC_FATAL_ERROR, &decimal_value, 0, 0, 0, str);
  return str;
}

my_decimal *Item_cache_decimal::val_decimal(my_decimal *val)
{
  DBUG_ASSERT(fixed);
  return &decimal_value;
}


5571 5572
void Item_cache_str::store(Item *item)
{
unknown's avatar
merge  
unknown committed
5573
  value_buff.set(buffer, sizeof(buffer), item->collation.collation);
5574
  value= item->str_result(&value_buff);
5575 5576
  if ((null_value= item->null_value))
    value= 0;
5577
  else if (value != &value_buff)
5578 5579 5580 5581 5582 5583 5584 5585 5586
  {
    /*
      We copy string value to avoid changing value if 'item' is table field
      in queries like following (where t1.c is varchar):
      select a, 
             (select a,b,c from t1 where t1.a=t2.a) = ROW(a,2,'a'),
             (select c from t1 where a=t2.a)
        from t2;
    */
5587 5588
    value_buff.copy(*value);
    value= &value_buff;
5589 5590
  }
}
5591

5592
double Item_cache_str::val_real()
5593 5594
{
  DBUG_ASSERT(fixed == 1);
5595 5596
  int err_not_used;
  char *end_not_used;
5597
  if (value)
5598
    return my_strntod(value->charset(), (char*) value->ptr(),
5599 5600
		      value->length(), &end_not_used, &err_not_used);
  return (double) 0;
5601
}
5602 5603


5604 5605
longlong Item_cache_str::val_int()
{
5606
  DBUG_ASSERT(fixed == 1);
5607
  int err;
5608 5609
  if (value)
    return my_strntoll(value->charset(), value->ptr(),
5610
		       value->length(), 10, (char**) 0, &err);
5611 5612 5613
  else
    return (longlong)0;
}
unknown's avatar
unknown committed
5614

unknown's avatar
unknown committed
5615 5616 5617 5618 5619 5620 5621 5622 5623 5624
my_decimal *Item_cache_str::val_decimal(my_decimal *decimal_val)
{
  DBUG_ASSERT(fixed == 1);
  if (value)
    string2my_decimal(E_DEC_FATAL_ERROR, value, decimal_val);
  else
    decimal_val= 0;
  return decimal_val;
}

5625

unknown's avatar
unknown committed
5626 5627
bool Item_cache_row::allocate(uint num)
{
unknown's avatar
unknown committed
5628
  item_count= num;
unknown's avatar
unknown committed
5629
  THD *thd= current_thd;
unknown's avatar
unknown committed
5630 5631
  return (!(values= 
	    (Item_cache **) thd->calloc(sizeof(Item_cache *)*item_count)));
unknown's avatar
unknown committed
5632 5633
}

5634

unknown's avatar
unknown committed
5635 5636
bool Item_cache_row::setup(Item * item)
{
unknown's avatar
unknown committed
5637
  example= item;
unknown's avatar
unknown committed
5638 5639
  if (!values && allocate(item->cols()))
    return 1;
unknown's avatar
unknown committed
5640
  for (uint i= 0; i < item_count; i++)
unknown's avatar
unknown committed
5641
  {
unknown's avatar
unknown committed
5642
    Item *el= item->el(i);
unknown's avatar
unknown committed
5643 5644
    Item_cache *tmp;
    if (!(tmp= values[i]= Item_cache::get_cache(el->result_type())))
unknown's avatar
unknown committed
5645
      return 1;
unknown's avatar
unknown committed
5646
    tmp->setup(el);
unknown's avatar
unknown committed
5647 5648 5649 5650
  }
  return 0;
}

5651

unknown's avatar
unknown committed
5652 5653 5654 5655
void Item_cache_row::store(Item * item)
{
  null_value= 0;
  item->bring_value();
unknown's avatar
unknown committed
5656
  for (uint i= 0; i < item_count; i++)
unknown's avatar
unknown committed
5657 5658 5659 5660 5661 5662
  {
    values[i]->store(item->el(i));
    null_value|= values[i]->null_value;
  }
}

5663

unknown's avatar
unknown committed
5664 5665 5666 5667 5668
void Item_cache_row::illegal_method_call(const char *method)
{
  DBUG_ENTER("Item_cache_row::illegal_method_call");
  DBUG_PRINT("error", ("!!! %s method was called for row item", method));
  DBUG_ASSERT(0);
unknown's avatar
unknown committed
5669
  my_error(ER_OPERAND_COLUMNS, MYF(0), 1);
unknown's avatar
unknown committed
5670 5671 5672
  DBUG_VOID_RETURN;
}

5673

unknown's avatar
unknown committed
5674 5675
bool Item_cache_row::check_cols(uint c)
{
unknown's avatar
unknown committed
5676
  if (c != item_count)
unknown's avatar
unknown committed
5677
  {
unknown's avatar
unknown committed
5678
    my_error(ER_OPERAND_COLUMNS, MYF(0), c);
unknown's avatar
unknown committed
5679 5680 5681 5682 5683
    return 1;
  }
  return 0;
}

5684

unknown's avatar
unknown committed
5685 5686
bool Item_cache_row::null_inside()
{
unknown's avatar
unknown committed
5687
  for (uint i= 0; i < item_count; i++)
unknown's avatar
unknown committed
5688 5689 5690 5691 5692 5693 5694 5695 5696 5697 5698 5699 5700 5701 5702 5703
  {
    if (values[i]->cols() > 1)
    {
      if (values[i]->null_inside())
	return 1;
    }
    else
    {
      values[i]->val_int();
      if (values[i]->null_value)
	return 1;
    }
  }
  return 0;
}

5704

unknown's avatar
unknown committed
5705 5706
void Item_cache_row::bring_value()
{
unknown's avatar
unknown committed
5707
  for (uint i= 0; i < item_count; i++)
unknown's avatar
unknown committed
5708 5709 5710
    values[i]->bring_value();
  return;
}
unknown's avatar
unknown committed
5711

5712

5713 5714
Item_type_holder::Item_type_holder(THD *thd, Item *item)
  :Item(thd, item), enum_set_typelib(0), fld_type(get_real_type(item))
5715 5716
{
  DBUG_ASSERT(item->fixed);
unknown's avatar
unknown committed
5717

5718
  max_length= display_length(item);
5719
  maybe_null= item->maybe_null;
5720
  collation.set(item->collation);
5721
  get_full_info(item);
unknown's avatar
unknown committed
5722 5723 5724
  /* fix variable decimals which always is NOT_FIXED_DEC */
  if (Field::result_merge_type(fld_type) == INT_RESULT)
    decimals= 0;
unknown's avatar
unknown committed
5725
  prev_decimal_int_part= item->decimal_int_part();
5726 5727 5728
}


5729
/*
5730
  Return expression type of Item_type_holder
5731 5732

  SYNOPSIS
5733
    Item_type_holder::result_type()
5734 5735

  RETURN
5736
     Item_result (type of internal MySQL expression result)
5737 5738
*/

5739
Item_result Item_type_holder::result_type() const
5740
{
5741
  return Field::result_merge_type(fld_type);
5742
}
5743

5744

unknown's avatar
unknown committed
5745
/*
5746
  Find real field type of item
unknown's avatar
unknown committed
5747 5748

  SYNOPSIS
5749
    Item_type_holder::get_real_type()
unknown's avatar
unknown committed
5750 5751

  RETURN
5752
    type of field which should be created to store item value
unknown's avatar
unknown committed
5753 5754
*/

5755
enum_field_types Item_type_holder::get_real_type(Item *item)
5756
{
5757
  switch(item->type())
5758
  {
5759
  case FIELD_ITEM:
5760
  {
unknown's avatar
unknown committed
5761
    /*
5762 5763
      Item_fields::field_type ask Field_type() but sometimes field return
      a different type, like for enum/set, so we need to ask real type.
unknown's avatar
unknown committed
5764
    */
5765 5766 5767 5768 5769 5770
    Field *field= ((Item_field *) item)->field;
    enum_field_types type= field->real_type();
    /* work around about varchar type field detection */
    if (type == MYSQL_TYPE_STRING && field->type() == MYSQL_TYPE_VAR_STRING)
      return MYSQL_TYPE_VAR_STRING;
    return type;
5771
  }
5772
  case SUM_FUNC_ITEM:
5773
  {
5774 5775 5776 5777
    /*
      Argument of aggregate function sometimes should be asked about field
      type
    */
5778 5779
    Item_sum *item_sum= (Item_sum *) item;
    if (item_sum->keep_field_type())
5780 5781 5782 5783
      return get_real_type(item_sum->args[0]);
    break;
  }
  case FUNC_ITEM:
unknown's avatar
unknown committed
5784
    if (((Item_func *) item)->functype() == Item_func::GUSERVAR_FUNC)
5785
    {
5786
      /*
5787 5788 5789 5790
        There are work around of problem with changing variable type on the
        fly and variable always report "string" as field type to get
        acceptable information for client in send_field, so we make field
        type from expression type.
5791
      */
unknown's avatar
unknown committed
5792
      switch (item->result_type()) {
5793 5794 5795 5796 5797 5798
      case STRING_RESULT:
        return MYSQL_TYPE_VAR_STRING;
      case INT_RESULT:
        return MYSQL_TYPE_LONGLONG;
      case REAL_RESULT:
        return MYSQL_TYPE_DOUBLE;
unknown's avatar
unknown committed
5799 5800
      case DECIMAL_RESULT:
        return MYSQL_TYPE_NEWDECIMAL;
5801 5802 5803 5804 5805
      case ROW_RESULT:
      default:
        DBUG_ASSERT(0);
        return MYSQL_TYPE_VAR_STRING;
      }
5806
    }
5807 5808 5809
    break;
  default:
    break;
5810
  }
5811
  return item->field_type();
5812 5813
}

5814
/*
5815 5816
  Find field type which can carry current Item_type_holder type and
  type of given Item.
5817 5818

  SYNOPSIS
5819 5820 5821
    Item_type_holder::join_types()
    thd     thread handler
    item    given item to join its parameters with this item ones
5822 5823

  RETURN
5824 5825
    TRUE   error - types are incompatible
    FALSE  OK
5826 5827
*/

5828
bool Item_type_holder::join_types(THD *thd, Item *item)
5829
{
unknown's avatar
unknown committed
5830 5831
  uint max_length_orig= max_length;
  uint decimals_orig= decimals;
unknown's avatar
unknown committed
5832 5833 5834 5835 5836 5837 5838
  DBUG_ENTER("Item_type_holder::join_types");
  DBUG_PRINT("info:", ("was type %d len %d, dec %d name %s",
                       fld_type, max_length, decimals,
                       (name ? name : "<NULL>")));
  DBUG_PRINT("info:", ("in type %d len %d, dec %d",
                       get_real_type(item),
                       item->max_length, item->decimals));
5839
  fld_type= Field::field_type_merge(fld_type, get_real_type(item));
5840
  {
unknown's avatar
unknown committed
5841 5842 5843 5844 5845
    int item_decimals= item->decimals;
    /* fix variable decimals which always is NOT_FIXED_DEC */
    if (Field::result_merge_type(fld_type) == INT_RESULT)
      item_decimals= 0;
    decimals= max(decimals, item_decimals);
5846
  }
unknown's avatar
unknown committed
5847
  if (Field::result_merge_type(fld_type) == DECIMAL_RESULT)
5848
  {
unknown's avatar
unknown committed
5849 5850 5851 5852 5853 5854
    decimals= min(max(decimals, item->decimals), DECIMAL_MAX_SCALE);
    int precision= min(max(prev_decimal_int_part, item->decimal_int_part())
                       + decimals, DECIMAL_MAX_PRECISION);
    unsigned_flag&= item->unsigned_flag;
    max_length= my_decimal_precision_to_length(precision, decimals,
                                               unsigned_flag);
5855
  }
unknown's avatar
unknown committed
5856 5857
  else
    max_length= max(max_length, display_length(item));
unknown's avatar
unknown committed
5858
 
unknown's avatar
unknown committed
5859 5860 5861
  switch (Field::result_merge_type(fld_type))
  {
  case STRING_RESULT:
5862
  {
5863
    const char *old_cs, *old_derivation;
5864 5865
    old_cs= collation.collation->name;
    old_derivation= collation.derivation_name();
5866
    if (collation.aggregate(item->collation))
5867
    {
5868
      my_error(ER_CANT_AGGREGATE_2COLLATIONS, MYF(0),
5869 5870 5871 5872
	       old_cs, old_derivation,
	       item->collation.collation->name,
	       item->collation.derivation_name(),
	       "UNION");
unknown's avatar
unknown committed
5873
      DBUG_RETURN(TRUE);
5874
    }
unknown's avatar
unknown committed
5875
    break;
5876
  }
unknown's avatar
unknown committed
5877 5878 5879 5880 5881 5882
  case REAL_RESULT:
  {
    if (decimals != NOT_FIXED_DEC)
    {
      int delta1= max_length_orig - decimals_orig;
      int delta2= item->max_length - item->decimals;
5883 5884 5885 5886 5887
      if (fld_type == MYSQL_TYPE_DECIMAL)
        max_length= max(delta1, delta2) + decimals;
      else
        max_length= min(max(delta1, delta2) + decimals,
                        (fld_type == MYSQL_TYPE_FLOAT) ? FLT_DIG+6 : DBL_DIG+7);
unknown's avatar
unknown committed
5888 5889 5890 5891
    }
    else
      max_length= (fld_type == MYSQL_TYPE_FLOAT) ? FLT_DIG+6 : DBL_DIG+7;
    break;
5892
  }
unknown's avatar
unknown committed
5893 5894
  default:;
  };
5895 5896
  maybe_null|= item->maybe_null;
  get_full_info(item);
unknown's avatar
unknown committed
5897 5898 5899

  /* Remember decimal integer part to be used in DECIMAL_RESULT handleng */
  prev_decimal_int_part= decimal_int_part();
5900 5901
  DBUG_PRINT("info", ("become type: %d  len: %u  dec: %u",
                      (int) fld_type, max_length, (uint) decimals));
unknown's avatar
unknown committed
5902
  DBUG_RETURN(FALSE);
5903 5904
}

5905 5906
/*
  Calculate lenth for merging result for given Item type
5907

5908 5909 5910
  SYNOPSIS
    Item_type_holder::real_length()
    item  Item for lrngth detection
5911

5912 5913 5914
  RETURN
    length
*/
5915

5916
uint32 Item_type_holder::display_length(Item *item)
5917 5918
{
  if (item->type() == Item::FIELD_ITEM)
unknown's avatar
unknown committed
5919
    return ((Item_field *)item)->max_disp_length();
5920

5921
  switch (item->field_type())
5922
  {
5923 5924 5925 5926 5927 5928 5929
  case MYSQL_TYPE_DECIMAL:
  case MYSQL_TYPE_TIMESTAMP:
  case MYSQL_TYPE_DATE:
  case MYSQL_TYPE_TIME:
  case MYSQL_TYPE_DATETIME:
  case MYSQL_TYPE_YEAR:
  case MYSQL_TYPE_NEWDATE:
unknown's avatar
unknown committed
5930 5931 5932
  case MYSQL_TYPE_VARCHAR:
  case MYSQL_TYPE_BIT:
  case MYSQL_TYPE_NEWDECIMAL:
5933 5934 5935 5936 5937 5938 5939 5940 5941
  case MYSQL_TYPE_ENUM:
  case MYSQL_TYPE_SET:
  case MYSQL_TYPE_TINY_BLOB:
  case MYSQL_TYPE_MEDIUM_BLOB:
  case MYSQL_TYPE_LONG_BLOB:
  case MYSQL_TYPE_BLOB:
  case MYSQL_TYPE_VAR_STRING:
  case MYSQL_TYPE_STRING:
  case MYSQL_TYPE_GEOMETRY:
5942
    return item->max_length;
5943 5944 5945 5946 5947 5948 5949 5950 5951
  case MYSQL_TYPE_TINY:
    return 4;
  case MYSQL_TYPE_SHORT:
    return 6;
  case MYSQL_TYPE_LONG:
    return 11;
  case MYSQL_TYPE_FLOAT:
    return 25;
  case MYSQL_TYPE_DOUBLE:
5952
    return 53;
5953 5954 5955
  case MYSQL_TYPE_NULL:
    return 4;
  case MYSQL_TYPE_LONGLONG:
5956
    return 20;
5957 5958
  case MYSQL_TYPE_INT24:
    return 8;
5959 5960 5961 5962 5963
  default:
    DBUG_ASSERT(0); // we should never go there
    return 0;
  }
}
5964

5965 5966 5967 5968 5969 5970 5971 5972 5973 5974 5975 5976 5977 5978 5979

/*
  Make temporary table field according collected information about type
  of UNION result

  SYNOPSIS
    Item_type_holder::make_field_by_type()
    table  temporary table for which we create fields

  RETURN
    created field
*/

Field *Item_type_holder::make_field_by_type(TABLE *table)
{
unknown's avatar
unknown committed
5980 5981 5982 5983 5984
  /*
    The field functions defines a field to be not null if null_ptr is not 0
  */
  uchar *null_ptr= maybe_null ? (uchar*) "" : 0;
  switch (fld_type)
5985
  {
unknown's avatar
unknown committed
5986
  case MYSQL_TYPE_ENUM:
5987
    DBUG_ASSERT(enum_set_typelib);
unknown's avatar
unknown committed
5988 5989 5990 5991 5992 5993 5994 5995 5996 5997 5998 5999
    return new Field_enum((char *) 0, max_length, null_ptr, 0,
                          Field::NONE, name,
                          table, get_enum_pack_length(enum_set_typelib->count),
                          enum_set_typelib, collation.collation);
  case MYSQL_TYPE_SET:
    DBUG_ASSERT(enum_set_typelib);
    return new Field_set((char *) 0, max_length, null_ptr, 0,
                         Field::NONE, name,
                         table, get_set_pack_length(enum_set_typelib->count),
                         enum_set_typelib, collation.collation);
  default:
    break;
6000 6001 6002 6003 6004 6005 6006 6007 6008 6009 6010 6011 6012 6013 6014 6015 6016 6017
  }
  return tmp_table_field_from_field_type(table);
}


/*
  Get full information from Item about enum/set fields to be able to create
  them later

  SYNOPSIS
    Item_type_holder::get_full_info
    item    Item for information collection
*/
void Item_type_holder::get_full_info(Item *item)
{
  if (fld_type == MYSQL_TYPE_ENUM ||
      fld_type == MYSQL_TYPE_SET)
  {
6018 6019 6020 6021
    if (item->type() == Item::SUM_FUNC_ITEM &&
        (((Item_sum*)item)->sum_func() == Item_sum::MAX_FUNC ||
         ((Item_sum*)item)->sum_func() == Item_sum::MIN_FUNC))
      item = ((Item_sum*)item)->args[0];
6022
    /*
6023 6024
      We can have enum/set type after merging only if we have one enum|set
      field (or MIN|MAX(enum|set field)) and number of NULL fields
6025 6026 6027 6028 6029 6030 6031 6032 6033 6034 6035 6036 6037 6038 6039 6040
    */
    DBUG_ASSERT((enum_set_typelib &&
                 get_real_type(item) == MYSQL_TYPE_NULL) ||
                (!enum_set_typelib &&
                 item->type() == Item::FIELD_ITEM &&
                 (get_real_type(item) == MYSQL_TYPE_ENUM ||
                  get_real_type(item) == MYSQL_TYPE_SET) &&
                 ((Field_enum*)((Item_field *) item)->field)->typelib));
    if (!enum_set_typelib)
    {
      enum_set_typelib= ((Field_enum*)((Item_field *) item)->field)->typelib;
    }
  }
}


6041
double Item_type_holder::val_real()
6042 6043 6044 6045 6046 6047 6048 6049 6050 6051 6052 6053
{
  DBUG_ASSERT(0); // should never be called
  return 0.0;
}


longlong Item_type_holder::val_int()
{
  DBUG_ASSERT(0); // should never be called
  return 0;
}

unknown's avatar
unknown committed
6054 6055 6056 6057 6058
my_decimal *Item_type_holder::val_decimal(my_decimal *)
{
  DBUG_ASSERT(0); // should never be called
  return 0;
}
6059 6060 6061 6062 6063 6064 6065

String *Item_type_holder::val_str(String*)
{
  DBUG_ASSERT(0); // should never be called
  return 0;
}

6066 6067 6068 6069 6070 6071 6072 6073
void Item_result_field::cleanup()
{
  DBUG_ENTER("Item_result_field::cleanup()");
  Item::cleanup();
  result_field= 0;
  DBUG_VOID_RETURN;
}

6074 6075 6076 6077 6078 6079 6080 6081 6082 6083 6084 6085 6086 6087 6088 6089 6090 6091 6092 6093 6094 6095 6096 6097 6098 6099 6100 6101
/*
  Dummy error processor used by default by Name_resolution_context

  SYNOPSIS
    dummy_error_processor()

  NOTE
    do nothing
*/

void dummy_error_processor(THD *thd, void *data)
{}

/*
  Wrapper of hide_view_error call for Name_resolution_context error processor

  SYNOPSIS
    view_error_processor()

  NOTE
    hide view underlying tables details in error messages
*/

void view_error_processor(THD *thd, void *data)
{
  ((TABLE_LIST *)data)->hide_view_error(thd);
}

unknown's avatar
unknown committed
6102 6103 6104 6105
/*****************************************************************************
** Instantiate templates
*****************************************************************************/

6106
#ifdef HAVE_EXPLICIT_TEMPLATE_INSTANTIATION
unknown's avatar
unknown committed
6107 6108
template class List<Item>;
template class List_iterator<Item>;
unknown's avatar
unknown committed
6109
template class List_iterator_fast<Item>;
6110
template class List_iterator_fast<Item_field>;
unknown's avatar
unknown committed
6111 6112
template class List<List_item>;
#endif