item_cmpfunc.cc 130 KB
Newer Older
unknown's avatar
unknown committed
1
/* Copyright (C) 2000-2006 MySQL AB
unknown's avatar
unknown committed
2

unknown's avatar
unknown committed
3 4
   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
unknown's avatar
unknown committed
5
   the Free Software Foundation; version 2 of the License.
unknown's avatar
unknown committed
6

unknown's avatar
unknown committed
7 8 9 10
   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
11

unknown's avatar
unknown committed
12 13 14 15 16 17 18
   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 */


/* This file defines all compare functions */

19
#ifdef USE_PRAGMA_IMPLEMENTATION
unknown's avatar
unknown committed
20 21 22 23 24
#pragma implementation				// gcc: Class implementation
#endif

#include "mysql_priv.h"
#include <m_ctype.h>
25
#include "sql_select.h"
26

27 28
static bool convert_constant_item(THD *thd, Field *field, Item **item);

29 30
static Item_result item_store_type(Item_result a, Item *item,
                                   my_bool unsigned_flag)
31
{
32 33
  Item_result b= item->result_type();

34 35 36 37
  if (a == STRING_RESULT || b == STRING_RESULT)
    return STRING_RESULT;
  else if (a == REAL_RESULT || b == REAL_RESULT)
    return REAL_RESULT;
38 39
  else if (a == DECIMAL_RESULT || b == DECIMAL_RESULT ||
           unsigned_flag != item->unsigned_flag)
unknown's avatar
unknown committed
40
    return DECIMAL_RESULT;
41 42 43 44 45 46
  else
    return INT_RESULT;
}

static void agg_result_type(Item_result *type, Item **items, uint nitems)
{
47
  Item **item, **item_end;
48
  my_bool unsigned_flag= 0;
49 50 51 52

  *type= STRING_RESULT;
  /* Skip beginning NULL items */
  for (item= items, item_end= item + nitems; item < item_end; item++)
53
  {
54 55 56
    if ((*item)->type() != Item::NULL_ITEM)
    {
      *type= (*item)->result_type();
57
      unsigned_flag= (*item)->unsigned_flag;
58 59 60
      item++;
      break;
    }
61 62
  }
  /* Combine result types. Note: NULL items don't affect the result */
63
  for (; item < item_end; item++)
64
  {
65
    if ((*item)->type() != Item::NULL_ITEM)
66
      *type= item_store_type(*type, *item, unsigned_flag);
67
  }
68 69
}

70

71
/*
72
  Compare row signature of two expressions
73

74 75 76 77
  SYNOPSIS:
    cmp_row_type()
    item1          the first expression
    item2         the second expression
78 79

  DESCRIPTION
80 81 82 83 84 85 86 87 88
    The function checks that two expressions have compatible row signatures
    i.e. that the number of columns they return are the same and that if they
    are both row expressions then each component from the first expression has 
    a row signature compatible with the signature of the corresponding component
    of the second expression.

  RETURN VALUES
    1  type incompatibility has been detected
    0  otherwise
89 90
*/

91
static int cmp_row_type(Item* item1, Item* item2)
92
{
93 94 95 96 97
  uint n= item1->cols();
  if (item2->check_cols(n))
    return 1;
  for (uint i=0; i<n; i++)
  {
unknown's avatar
unknown committed
98 99 100
    if (item2->element_index(i)->check_cols(item1->element_index(i)->cols()) ||
        (item1->element_index(i)->result_type() == ROW_RESULT &&
         cmp_row_type(item1->element_index(i), item2->element_index(i))))
101 102 103
      return 1;
  }
  return 0;
104 105 106 107
}


/*
108
  Aggregates result types from the array of items.
109

110 111 112 113 114
  SYNOPSIS:
    agg_cmp_type()
    type   [out] the aggregated type
    items        array of items to aggregate the type from
    nitems       number of items in the array
115 116

  DESCRIPTION
117 118 119
    This function aggregates result types from the array of items. Found type
    supposed to be used later for comparison of values of these items.
    Aggregation itself is performed by the item_cmp_type() function.
120 121
    The function also checks compatibility of row signatures for the
    submitted items (see the spec for the cmp_row_type function). 
122

123 124 125
  RETURN VALUES
    1  type incompatibility has been detected
    0  otherwise
126 127
*/

unknown's avatar
unknown committed
128
static int agg_cmp_type(Item_result *type, Item **items, uint nitems)
129 130
{
  uint i;
131 132
  type[0]= items[0]->result_type();
  for (i= 1 ; i < nitems ; i++)
133
  {
134
    type[0]= item_cmp_type(type[0], items[i]->result_type());
135 136 137 138 139 140 141 142 143 144 145
    /*
      When aggregating types of two row expressions we have to check
      that they have the same cardinality and that each component
      of the first row expression has a compatible row signature with
      the signature of the corresponding component of the second row
      expression.
    */ 
    if (type[0] == ROW_RESULT && cmp_row_type(items[0], items[i]))
      return 1;     // error found: invalid usage of rows
  }
  return 0;
146 147
}

148

149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177
/**
  @brief Aggregates field types from the array of items.

  @param[in] items  array of items to aggregate the type from
  @paran[in] nitems number of items in the array

  @details This function aggregates field types from the array of items.
    Found type is supposed to be used later as the result field type
    of a multi-argument function.
    Aggregation itself is performed by the Field::field_type_merge()
    function.

  @note The term "aggregation" is used here in the sense of inferring the
    result type of a function from its argument types.

  @return aggregated field type.
*/

enum_field_types agg_field_type(Item **items, uint nitems)
{
  uint i;
  if (!nitems || items[0]->result_type() == ROW_RESULT )
    return (enum_field_types)-1;
  enum_field_types res= items[0]->field_type();
  for (i= 1 ; i < nitems ; i++)
    res= Field::field_type_merge(res, items[i]->field_type());
  return res;
}

unknown's avatar
unknown committed
178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213
/*
  Collects different types for comparison of first item with each other items

  SYNOPSIS
    collect_cmp_types()
      items             Array of items to collect types from
      nitems            Number of items in the array

  DESCRIPTION
    This function collects different result types for comparison of the first
    item in the list with each of the remaining items in the 'items' array.

  RETURN
    0 - if row type incompatibility has been detected (see cmp_row_type)
    Bitmap of collected types - otherwise
*/

static uint collect_cmp_types(Item **items, uint nitems)
{
  uint i;
  uint found_types;
  Item_result left_result= items[0]->result_type();
  DBUG_ASSERT(nitems > 1);
  found_types= 0;
  for (i= 1; i < nitems ; i++)
  {
    if ((left_result == ROW_RESULT || 
         items[i]->result_type() == ROW_RESULT) &&
        cmp_row_type(items[0], items[i]))
      return 0;
    found_types|= 1<< (uint)item_cmp_type(left_result,
                                           items[i]->result_type());
  }
  return found_types;
}

unknown's avatar
unknown committed
214 215
static void my_coll_agg_error(DTCollation &c1, DTCollation &c2,
                              const char *fname)
216
{
217 218 219 220
  my_error(ER_CANT_AGGREGATE_2COLLATIONS, MYF(0),
           c1.collation->name,c1.derivation_name(),
           c2.collation->name,c2.derivation_name(),
           fname);
221 222
}

unknown's avatar
unknown committed
223 224

Item_bool_func2* Eq_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
225 226 227
{
  return new Item_func_eq(a, b);
}
unknown's avatar
unknown committed
228 229 230


Item_bool_func2* Ne_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
231 232 233
{
  return new Item_func_ne(a, b);
}
unknown's avatar
unknown committed
234 235 236


Item_bool_func2* Gt_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
237 238 239
{
  return new Item_func_gt(a, b);
}
unknown's avatar
unknown committed
240 241 242


Item_bool_func2* Lt_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
243 244 245
{
  return new Item_func_lt(a, b);
}
unknown's avatar
unknown committed
246 247 248


Item_bool_func2* Ge_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
249 250 251
{
  return new Item_func_ge(a, b);
}
unknown's avatar
unknown committed
252 253 254


Item_bool_func2* Le_creator::create(Item *a, Item *b) const
unknown's avatar
unknown committed
255 256 257
{
  return new Item_func_le(a, b);
}
unknown's avatar
unknown committed
258

unknown's avatar
unknown committed
259
/*
260
  Test functions
261 262
  Most of these  returns 0LL if false and 1LL if true and
  NULL if some arg is NULL.
unknown's avatar
unknown committed
263 264 265 266
*/

longlong Item_func_not::val_int()
{
267
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
268
  bool value= args[0]->val_bool();
unknown's avatar
unknown committed
269
  null_value=args[0]->null_value;
270
  return ((!null_value && value == 0) ? 1 : 0);
unknown's avatar
unknown committed
271 272
}

273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288
/*
  We put any NOT expression into parenthesis to avoid
  possible problems with internal view representations where
  any '!' is converted to NOT. It may cause a problem if
  '!' is used in an expression together with other operators
  whose precedence is lower than the precedence of '!' yet
  higher than the precedence of NOT.
*/

void Item_func_not::print(String *str)
{
  str->append('(');
  Item_func::print(str);
  str->append(')');
}

289 290 291 292 293
/*
  special NOT for ALL subquery
*/

longlong Item_func_not_all::val_int()
294 295
{
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
296
  bool value= args[0]->val_bool();
297 298

  /*
unknown's avatar
unknown committed
299 300
    return TRUE if there was records in underlying select in max/min
    optimization (ALL subquery)
301 302 303 304
  */
  if (empty_underlying_subquery())
    return 1;

305
  null_value= args[0]->null_value;
306 307 308 309 310 311 312 313
  return ((!null_value && value == 0) ? 1 : 0);
}


bool Item_func_not_all::empty_underlying_subquery()
{
  return ((test_sum_item && !test_sum_item->any_value()) ||
          (test_sub_item && !test_sub_item->any_value()));
314 315
}

unknown's avatar
unknown committed
316 317 318 319 320 321 322 323
void Item_func_not_all::print(String *str)
{
  if (show)
    Item_func::print(str);
  else
    args[0]->print(str);
}

324 325

/*
unknown's avatar
unknown committed
326
  Special NOP (No OPeration) for ALL subquery it is like  Item_func_not_all
unknown's avatar
unknown committed
327
  (return TRUE if underlying subquery do not return rows) but if subquery
unknown's avatar
unknown committed
328
  returns some rows it return same value as argument (TRUE/FALSE).
329 330 331 332 333
*/

longlong Item_func_nop_all::val_int()
{
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
334
  longlong value= args[0]->val_int();
335 336

  /*
unknown's avatar
unknown committed
337 338
    return FALSE if there was records in underlying select in max/min
    optimization (SAME/ANY subquery)
339 340
  */
  if (empty_underlying_subquery())
unknown's avatar
unknown committed
341
    return 0;
342 343 344 345 346 347

  null_value= args[0]->null_value;
  return (null_value || value == 0) ? 0 : 1;
}


unknown's avatar
unknown committed
348
/*
349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370
  Convert a constant item to an int and replace the original item

  SYNOPSIS
    convert_constant_item()
    thd             thread handle
    field           item will be converted using the type of this field
    item  [in/out]  reference to the item to convert

  DESCRIPTION
    The function converts a constant expression or string to an integer.
    On successful conversion the original item is substituted for the
    result of the item evaluation.
    This is done when comparing DATE/TIME of different formats and
    also when comparing bigint to strings (in which case strings
    are converted to bigints).

  NOTES
    This function is called only at prepare stage.
    As all derived tables are filled only after all derived tables
    are prepared we do not evaluate items with subselects here because
    they can contain derived tables and thus we may attempt to use a
    table that has not been populated yet.
unknown's avatar
unknown committed
371 372 373 374

  RESULT VALUES
  0	Can't convert item
  1	Item was replaced with an integer version of the item
unknown's avatar
unknown committed
375
*/
unknown's avatar
unknown committed
376

377
static bool convert_constant_item(THD *thd, Field *field, Item **item)
unknown's avatar
unknown committed
378
{
379
  int result= 0;
unknown's avatar
unknown committed
380

381
  if (!(*item)->with_subselect && (*item)->const_item())
unknown's avatar
unknown committed
382
  {
unknown's avatar
unknown committed
383 384
    TABLE *table= field->table;
    ulong orig_sql_mode= thd->variables.sql_mode;
385
    enum_check_fields orig_count_cuted_fields= thd->count_cuted_fields;
unknown's avatar
unknown committed
386 387 388
    my_bitmap_map *old_write_map;
    my_bitmap_map *old_read_map;

389 390 391
    LINT_INIT(old_write_map);
    LINT_INIT(old_read_map);

unknown's avatar
unknown committed
392 393 394 395 396
    if (table)
    {
      old_write_map= dbug_tmp_use_all_columns(table, table->write_set);
      old_read_map= dbug_tmp_use_all_columns(table, table->read_set);
    }
397
    /* For comparison purposes allow invalid dates like 2000-01-32 */
398 399
    thd->variables.sql_mode= (orig_sql_mode & ~MODE_NO_ZERO_DATE) | 
                             MODE_INVALID_DATES;
400
    thd->count_cuted_fields= CHECK_FIELD_IGNORE;
unknown's avatar
unknown committed
401
    if (!(*item)->is_null() && !(*item)->save_in_field(field, 1))
unknown's avatar
unknown committed
402
    {
403 404
      Item *tmp= new Item_int_with_ref(field->val_int(), *item,
                                       test(field->flags & UNSIGNED_FLAG));
405
      if (tmp)
406
        thd->change_item_tree(item, tmp);
407
      result= 1;					// Item was replaced
unknown's avatar
unknown committed
408
    }
unknown's avatar
unknown committed
409
    thd->variables.sql_mode= orig_sql_mode;
410
    thd->count_cuted_fields= orig_count_cuted_fields;
unknown's avatar
unknown committed
411 412 413 414 415
    if (table)
    {
      dbug_tmp_restore_column_map(table->write_set, old_write_map);
      dbug_tmp_restore_column_map(table->read_set, old_read_map);
    }
unknown's avatar
unknown committed
416
  }
417
  return result;
unknown's avatar
unknown committed
418 419
}

unknown's avatar
unknown committed
420

421 422 423
void Item_bool_func2::fix_length_and_dec()
{
  max_length= 1;				     // Function returns 0 or 1
424
  THD *thd;
425 426 427 428 429 430 431

  /*
    As some compare functions are generated after sql_yacc,
    we have to check for out of memory conditions here
  */
  if (!args[0] || !args[1])
    return;
432 433 434 435 436 437 438 439 440 441 442 443 444

  /* 
    We allow to convert to Unicode character sets in some cases.
    The conditions when conversion is possible are:
    - arguments A and B have different charsets
    - A wins according to coercibility rules
    - character set of A is superset for character set of B
   
    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.
  */

445
  
446 447 448
  DTCollation coll;
  if (args[0]->result_type() == STRING_RESULT &&
      args[1]->result_type() == STRING_RESULT &&
449
      agg_arg_charsets(coll, args, 2, MY_COLL_CMP_CONV, 1))
unknown's avatar
unknown committed
450
    return;
451
    
452 453
  args[0]->cmp_context= args[1]->cmp_context=
    item_cmp_type(args[0]->result_type(), args[1]->result_type());
unknown's avatar
unknown committed
454
  // Make a special case of compare with fields to get nicer DATE comparisons
unknown's avatar
unknown committed
455 456 457 458 459 460

  if (functype() == LIKE_FUNC)  // Disable conversion in case of LIKE function.
  {
    set_cmp_func();
    return;
  }
461

462
  thd= current_thd;
463
  if (!thd->is_context_analysis_only())
unknown's avatar
unknown committed
464
  {
465 466
    Item *arg_real_item= args[0]->real_item();
    if (arg_real_item->type() == FIELD_ITEM)
unknown's avatar
unknown committed
467
    {
468
      Field *field=((Item_field*) arg_real_item)->field;
469 470 471
      if (field->can_be_compared_as_longlong() &&
          !(arg_real_item->is_datetime() &&
            args[1]->result_type() == STRING_RESULT))
unknown's avatar
unknown committed
472
      {
473 474 475 476
        if (convert_constant_item(thd, field,&args[1]))
        {
          cmp.set_cmp_func(this, tmp_arg, tmp_arg+1,
                           INT_RESULT);		// Works for all types.
477
          args[0]->cmp_context= args[1]->cmp_context= INT_RESULT;
478 479
          return;
        }
unknown's avatar
unknown committed
480 481
      }
    }
482 483
    arg_real_item= args[1]->real_item();
    if (arg_real_item->type() == FIELD_ITEM)
unknown's avatar
unknown committed
484
    {
485
      Field *field=((Item_field*) arg_real_item)->field;
486 487 488
      if (field->can_be_compared_as_longlong() &&
          !(arg_real_item->is_datetime() &&
            args[0]->result_type() == STRING_RESULT))
unknown's avatar
unknown committed
489
      {
490 491 492 493
        if (convert_constant_item(thd, field,&args[0]))
        {
          cmp.set_cmp_func(this, tmp_arg, tmp_arg+1,
                           INT_RESULT); // Works for all types.
494
          args[0]->cmp_context= args[1]->cmp_context= INT_RESULT;
495 496
          return;
        }
unknown's avatar
unknown committed
497 498 499
      }
    }
  }
500
  set_cmp_func();
unknown's avatar
unknown committed
501 502
}

503

504
int Arg_comparator::set_compare_func(Item_bool_func2 *item, Item_result type)
unknown's avatar
unknown committed
505
{
506
  owner= item;
unknown's avatar
unknown committed
507 508
  func= comparator_matrix[type]
                         [test(owner->functype() == Item_func::EQUAL_FUNC)];
unknown's avatar
unknown committed
509
  switch (type) {
unknown's avatar
unknown committed
510
  case ROW_RESULT:
unknown's avatar
unknown committed
511
  {
512 513
    uint n= (*a)->cols();
    if (n != (*b)->cols())
514
    {
unknown's avatar
unknown committed
515
      my_error(ER_OPERAND_COLUMNS, MYF(0), n);
516 517 518
      comparators= 0;
      return 1;
    }
519
    if (!(comparators= new Arg_comparator[n]))
unknown's avatar
unknown committed
520 521 522
      return 1;
    for (uint i=0; i < n; i++)
    {
523
      if ((*a)->element_index(i)->cols() != (*b)->element_index(i)->cols())
unknown's avatar
unknown committed
524
      {
525
	my_error(ER_OPERAND_COLUMNS, MYF(0), (*a)->element_index(i)->cols());
unknown's avatar
unknown committed
526
	return 1;
unknown's avatar
unknown committed
527
      }
unknown's avatar
unknown committed
528 529
      comparators[i].set_cmp_func(owner, (*a)->addr(i), (*b)->addr(i));
    }
unknown's avatar
unknown committed
530
    break;
531
  }
unknown's avatar
unknown committed
532
  case STRING_RESULT:
533 534 535 536 537
  {
    /*
      We must set cmp_charset here as we may be called from for an automatic
      generated item, like in natural join
    */
538 539
    if (cmp_collation.set((*a)->collation, (*b)->collation) || 
	cmp_collation.derivation == DERIVATION_NONE)
540 541 542 543
    {
      my_coll_agg_error((*a)->collation, (*b)->collation, owner->func_name());
      return 1;
    }
544
    if (cmp_collation.collation == &my_charset_bin)
unknown's avatar
unknown committed
545 546
    {
      /*
547
	We are using BLOB/BINARY/VARBINARY, change to compare byte by byte,
unknown's avatar
unknown committed
548 549 550 551 552 553
	without removing end space
      */
      if (func == &Arg_comparator::compare_string)
	func= &Arg_comparator::compare_binary_string;
      else if (func == &Arg_comparator::compare_e_string)
	func= &Arg_comparator::compare_e_binary_string;
unknown's avatar
unknown committed
554 555

      /*
unknown's avatar
unknown committed
556
        As this is binary compassion, mark all fields that they can't be
unknown's avatar
unknown committed
557 558 559 560 561 562
        transformed. Otherwise we would get into trouble with comparisons
        like:
        WHERE col= 'j' AND col LIKE BINARY 'j'
        which would be transformed to:
        WHERE col= 'j'
      */
563 564
      (*a)->walk(&Item::set_no_const_sub, FALSE, (uchar*) 0);
      (*b)->walk(&Item::set_no_const_sub, FALSE, (uchar*) 0);
unknown's avatar
unknown committed
565
    }
unknown's avatar
unknown committed
566
    break;
567
  }
unknown's avatar
unknown committed
568
  case INT_RESULT:
569
  {
570
    if (func == &Arg_comparator::compare_int_signed)
571 572
    {
      if ((*a)->unsigned_flag)
unknown's avatar
unknown committed
573 574 575
        func= (((*b)->unsigned_flag)?
               &Arg_comparator::compare_int_unsigned :
               &Arg_comparator::compare_int_unsigned_signed);
576 577 578
      else if ((*b)->unsigned_flag)
        func= &Arg_comparator::compare_int_signed_unsigned;
    }
579 580 581 582 583
    else if (func== &Arg_comparator::compare_e_int)
    {
      if ((*a)->unsigned_flag ^ (*b)->unsigned_flag)
        func= &Arg_comparator::compare_e_int_diff_signedness;
    }
unknown's avatar
unknown committed
584 585 586 587 588
    break;
  }
  case DECIMAL_RESULT:
    break;
  case REAL_RESULT:
589 590 591
  {
    if ((*a)->decimals < NOT_FIXED_DEC && (*b)->decimals < NOT_FIXED_DEC)
    {
592
      precision= 5 / log_10[max((*a)->decimals, (*b)->decimals) + 1];
593 594 595 596 597
      if (func == &Arg_comparator::compare_real)
        func= &Arg_comparator::compare_real_fixed;
      else if (func == &Arg_comparator::compare_e_real)
        func= &Arg_comparator::compare_e_real_fixed;
    }
unknown's avatar
unknown committed
598
    break;
unknown's avatar
unknown committed
599
  }
unknown's avatar
unknown committed
600 601
  default:
    DBUG_ASSERT(0);
602
  }
603
  return 0;
unknown's avatar
unknown committed
604
}
unknown's avatar
unknown committed
605

unknown's avatar
unknown committed
606

607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626
/**
  @brief Convert date provided in a string to the int representation.

  @param[in]   thd        thread handle
  @param[in]   str        a string to convert
  @param[in]   warn_type  type of the timestamp for issuing the warning
  @param[in]   warn_name  field name for issuing the warning
  @param[out]  error_arg  could not extract a DATE or DATETIME

  @details Convert date provided in the string str to the int
    representation.  If the string contains wrong date or doesn't
    contain it at all then a warning is issued.  The warn_type and
    the warn_name arguments are used as the name and the type of the
    field when issuing the warning.  If any input was discarded
    (trailing or non-timestampy characters), was_cut will be non-zero.
    was_type will return the type str_to_datetime() could correctly
    extract.

  @return
    converted value. 0 on error and on zero-dates -- check 'failure'
627 628 629 630 631 632
*/

static ulonglong
get_date_from_str(THD *thd, String *str, timestamp_type warn_type,
                  char *warn_name, bool *error_arg)
{
unknown's avatar
unknown committed
633
  ulonglong value= 0;
634 635 636 637 638 639 640 641 642
  int error;
  MYSQL_TIME l_time;
  enum_mysql_timestamp_type ret;

  ret= str_to_datetime(str->ptr(), str->length(), &l_time,
                       (TIME_FUZZY_DATE | MODE_INVALID_DATES |
                        (thd->variables.sql_mode &
                         (MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE))),
                       &error);
643 644

  if (ret == MYSQL_TIMESTAMP_DATETIME || ret == MYSQL_TIMESTAMP_DATE)
645
  {
646 647 648 649
    /*
      Do not return yet, we may still want to throw a "trailing garbage"
      warning.
    */
650
    *error_arg= FALSE;
651
    value= TIME_to_ulonglong_datetime(&l_time);
652
  }
653
  else
654
  {
655 656 657 658 659
    *error_arg= TRUE;
    error= 1;                                   /* force warning */
  }

  if (error > 0)
unknown's avatar
unknown committed
660 661 662
    make_truncated_value_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
                                 str->ptr(), str->length(),
                                 warn_type, warn_name);
663

664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728
  return value;
}


/*
  Check whether compare_datetime() can be used to compare items.

  SYNOPSIS
    Arg_comparator::can_compare_as_dates()
    a, b          [in]  items to be compared
    const_value   [out] converted value of the string constant, if any

  DESCRIPTION
    Check several cases when the DATE/DATETIME comparator should be used.
    The following cases are checked:
      1. Both a and b is a DATE/DATETIME field/function returning string or
         int result.
      2. Only a or b is a DATE/DATETIME field/function returning string or
         int result and the other item (b or a) is an item with string result.
         If the second item is a constant one then it's checked to be
         convertible to the DATE/DATETIME type. If the constant can't be
         converted to a DATE/DATETIME then the compare_datetime() comparator
         isn't used and the warning about wrong DATE/DATETIME value is issued.
      In all other cases (date-[int|real|decimal]/[int|real|decimal]-date)
      the comparison is handled by other comparators.
    If the datetime comparator can be used and one the operands of the
    comparison is a string constant that was successfully converted to a
    DATE/DATETIME type then the result of the conversion is returned in the
    const_value if it is provided.  If there is no constant or
    compare_datetime() isn't applicable then the *const_value remains
    unchanged.

  RETURN
    the found type of date comparison
*/

enum Arg_comparator::enum_date_cmp_type
Arg_comparator::can_compare_as_dates(Item *a, Item *b, ulonglong *const_value)
{
  enum enum_date_cmp_type cmp_type= CMP_DATE_DFLT;
  Item *str_arg= 0, *date_arg= 0;

  if (a->type() == Item::ROW_ITEM || b->type() == Item::ROW_ITEM)
    return CMP_DATE_DFLT;

  if (a->is_datetime())
  {
    if (b->is_datetime())
      cmp_type= CMP_DATE_WITH_DATE;
    else if (b->result_type() == STRING_RESULT)
    {
      cmp_type= CMP_DATE_WITH_STR;
      date_arg= a;
      str_arg= b;
    }
  }
  else if (b->is_datetime() && a->result_type() == STRING_RESULT)
  {
    cmp_type= CMP_STR_WITH_DATE;
    date_arg= b;
    str_arg= a;
  }

  if (cmp_type != CMP_DATE_DFLT)
  {
729 730 731 732 733 734 735
    /*
      Do not cache GET_USER_VAR() function as its const_item() may return TRUE
      for the current thread but it still may change during the execution.
    */
    if (cmp_type != CMP_DATE_WITH_DATE && str_arg->const_item() &&
        (str_arg->type() != Item::FUNC_ITEM ||
        ((Item_func*)str_arg)->functype() != Item_func::GUSERVAR_FUNC))
736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757
    {
      THD *thd= current_thd;
      ulonglong value;
      bool error;
      String tmp, *str_val= 0;
      timestamp_type t_type= (date_arg->field_type() == MYSQL_TYPE_DATE ?
                              MYSQL_TIMESTAMP_DATE : MYSQL_TIMESTAMP_DATETIME);

      str_val= str_arg->val_str(&tmp);
      if (str_arg->null_value)
        return CMP_DATE_DFLT;
      value= get_date_from_str(thd, str_val, t_type, date_arg->name, &error);
      if (error)
        return CMP_DATE_DFLT;
      if (const_value)
        *const_value= value;
    }
  }
  return cmp_type;
}


unknown's avatar
unknown committed
758 759 760 761 762 763 764
/*
  Retrieves correct TIME value from the given item.

  SYNOPSIS
    get_time_value()
    thd                 thread handle
    item_arg   [in/out] item to retrieve TIME value from
unknown's avatar
unknown committed
765
    cache_arg  [in/out] pointer to place to store the cache item to
unknown's avatar
unknown committed
766 767 768 769 770 771 772 773 774
    warn_item  [in]     unused
    is_null    [out]    TRUE <=> the item_arg is null

  DESCRIPTION
    Retrieves the correct TIME value from given item for comparison by the
    compare_datetime() function.
    If item's result can be compared as longlong then its int value is used
    and a value returned by get_time function is used otherwise.
    If an item is a constant one then its value is cached and it isn't
unknown's avatar
unknown committed
775 776
    get parsed again. An Item_cache_int object is used for for cached values.
    It seamlessly substitutes the original item.  The cache item is marked as
unknown's avatar
unknown committed
777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798
    non-constant to prevent re-caching it again.

  RETURN
    obtained value
*/

ulonglong
get_time_value(THD *thd, Item ***item_arg, Item **cache_arg,
               Item *warn_item, bool *is_null)
{
  ulonglong value;
  Item *item= **item_arg;
  MYSQL_TIME ltime;

  if (item->result_as_longlong())
  {
    value= item->val_int();
    *is_null= item->null_value;
  }
  else
  {
    *is_null= item->get_time(&ltime);
unknown's avatar
unknown committed
799
    value= !*is_null ? TIME_to_ulonglong_datetime(&ltime) : 0;
unknown's avatar
unknown committed
800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818
  }
  /*
    Do not cache GET_USER_VAR() function as its const_item() may return TRUE
    for the current thread but it still may change during the execution.
  */
  if (item->const_item() && cache_arg && (item->type() != Item::FUNC_ITEM ||
      ((Item_func*)item)->functype() != Item_func::GUSERVAR_FUNC))
  {
    Item_cache_int *cache= new Item_cache_int();
    /* Mark the cache as non-const to prevent re-caching. */
    cache->set_used_tables(1);
    cache->store(item, value);
    *cache_arg= cache;
    *item_arg= cache_arg;
  }
  return value;
}


819 820 821 822 823
int Arg_comparator::set_cmp_func(Item_bool_func2 *owner_arg,
                                        Item **a1, Item **a2,
                                        Item_result type)
{
  enum enum_date_cmp_type cmp_type;
824
  ulonglong const_value= (ulonglong)-1;
825 826 827 828 829 830 831 832 833 834 835 836
  a= a1;
  b= a2;

  if ((cmp_type= can_compare_as_dates(*a, *b, &const_value)))
  {
    thd= current_thd;
    owner= owner_arg;
    a_type= (*a)->field_type();
    b_type= (*b)->field_type();
    a_cache= 0;
    b_cache= 0;

837
    if (const_value != (ulonglong)-1)
838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854
    {
      Item_cache_int *cache= new Item_cache_int();
      /* Mark the cache as non-const to prevent re-caching. */
      cache->set_used_tables(1);
      if (!(*a)->is_datetime())
      {
        cache->store((*a), const_value);
        a_cache= cache;
        a= (Item **)&a_cache;
      }
      else
      {
        cache->store((*b), const_value);
        b_cache= cache;
        b= (Item **)&b_cache;
      }
    }
855
    is_nulls_eq= test(owner && owner->functype() == Item_func::EQUAL_FUNC);
856
    func= &Arg_comparator::compare_datetime;
unknown's avatar
unknown committed
857
    get_value_func= &get_datetime_value;
858 859
    return 0;
  }
860 861 862 863 864 865
  else if (type == STRING_RESULT && (*a)->field_type() == MYSQL_TYPE_TIME &&
           (*b)->field_type() == MYSQL_TYPE_TIME)
  {
    /* Compare TIME values as integers. */
    thd= current_thd;
    owner= owner_arg;
unknown's avatar
unknown committed
866 867 868 869 870
    a_cache= 0;
    b_cache= 0;
    is_nulls_eq= test(owner && owner->functype() == Item_func::EQUAL_FUNC);
    func= &Arg_comparator::compare_datetime;
    get_value_func= &get_time_value;
871 872 873
    return 0;
  }

874 875 876 877
  return set_compare_func(owner_arg, type);
}


878 879 880 881 882 883 884 885 886 887 888 889 890
void Arg_comparator::set_datetime_cmp_func(Item **a1, Item **b1)
{
  thd= current_thd;
  /* A caller will handle null values by itself. */
  owner= NULL;
  a= a1;
  b= b1;
  a_type= (*a)->field_type();
  b_type= (*b)->field_type();
  a_cache= 0;
  b_cache= 0;
  is_nulls_eq= FALSE;
  func= &Arg_comparator::compare_datetime;
unknown's avatar
unknown committed
891
  get_value_func= &get_datetime_value;
892 893
}

unknown's avatar
unknown committed
894

895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923
/*
  Retrieves correct DATETIME value from given item.

  SYNOPSIS
    get_datetime_value()
    thd                 thread handle
    item_arg   [in/out] item to retrieve DATETIME value from
    cache_arg  [in/out] pointer to place to store the caching item to
    warn_item  [in]     item for issuing the conversion warning
    is_null    [out]    TRUE <=> the item_arg is null

  DESCRIPTION
    Retrieves the correct DATETIME value from given item for comparison by the
    compare_datetime() function.
    If item's result can be compared as longlong then its int value is used
    and its string value is used otherwise. Strings are always parsed and
    converted to int values by the get_date_from_str() function.
    This allows us to compare correctly string dates with missed insignificant
    zeros. If an item is a constant one then its value is cached and it isn't
    get parsed again. An Item_cache_int object is used for caching values. It
    seamlessly substitutes the original item.  The cache item is marked as
    non-constant to prevent re-caching it again.  In order to compare
    correctly DATE and DATETIME items the result of the former are treated as
    a DATETIME with zero time (00:00:00).

  RETURN
    obtained value
*/

924
ulonglong
925 926 927
get_datetime_value(THD *thd, Item ***item_arg, Item **cache_arg,
                   Item *warn_item, bool *is_null)
{
unknown's avatar
unknown committed
928
  ulonglong value= 0;
929 930 931 932 933 934 935
  String buf, *str= 0;
  Item *item= **item_arg;

  if (item->result_as_longlong())
  {
    value= item->val_int();
    *is_null= item->null_value;
936 937 938 939 940 941
    /*
      Item_date_add_interval may return MYSQL_TYPE_STRING as the result
      field type. To detect that the DATE value has been returned we
      compare it with 1000000L - any DATE value should be less than it.
    */
    if (item->field_type() == MYSQL_TYPE_DATE || value < 100000000L)
942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963
      value*= 1000000L;
  }
  else
  {
    str= item->val_str(&buf);
    *is_null= item->null_value;
  }
  if (*is_null)
    return -1;
  /*
    Convert strings to the integer DATE/DATETIME representation.
    Even if both dates provided in strings we can't compare them directly as
    strings as there is no warranty that they are correct and do not miss
    some insignificant zeros.
  */
  if (str)
  {
    bool error;
    enum_field_types f_type= warn_item->field_type();
    timestamp_type t_type= f_type ==
      MYSQL_TYPE_DATE ? MYSQL_TIMESTAMP_DATE : MYSQL_TIMESTAMP_DATETIME;
    value= get_date_from_str(thd, str, t_type, warn_item->name, &error);
964 965 966 967 968 969
    /*
      If str did not contain a valid date according to the current
      SQL_MODE, get_date_from_str() has already thrown a warning,
      and we don't want to throw NULL on invalid date (see 5.2.6
      "SQL modes" in the manual), so we're done here.
    */
970
  }
971 972 973 974 975 976
  /*
    Do not cache GET_USER_VAR() function as its const_item() may return TRUE
    for the current thread but it still may change during the execution.
  */
  if (item->const_item() && cache_arg && (item->type() != Item::FUNC_ITEM ||
      ((Item_func*)item)->functype() != Item_func::GUSERVAR_FUNC))
977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013
  {
    Item_cache_int *cache= new Item_cache_int();
    /* Mark the cache as non-const to prevent re-caching. */
    cache->set_used_tables(1);
    cache->store(item, value);
    *cache_arg= cache;
    *item_arg= cache_arg;
  }
  return value;
}

/*
  Compare items values as dates.

  SYNOPSIS
    Arg_comparator::compare_datetime()

  DESCRIPTION
    Compare items values as DATE/DATETIME for both EQUAL_FUNC and from other
    comparison functions. The correct DATETIME values are obtained
    with help of the get_datetime_value() function.

  RETURN
    If is_nulls_eq is TRUE:
       1    if items are equal or both are null
       0    otherwise
    If is_nulls_eq is FALSE:
      -1   a < b or one of items is null
       0   a == b
       1   a > b
*/

int Arg_comparator::compare_datetime()
{
  bool is_null= FALSE;
  ulonglong a_value, b_value;

unknown's avatar
unknown committed
1014 1015
  /* Get DATE/DATETIME/TIME value of the 'a' item. */
  a_value= (*get_value_func)(thd, &a, &a_cache, *b, &is_null);
1016 1017
  if (!is_nulls_eq && is_null)
  {
1018 1019
    if (owner)
      owner->null_value= 1;
1020 1021 1022
    return -1;
  }

unknown's avatar
unknown committed
1023 1024
  /* Get DATE/DATETIME/TIME value of the 'b' item. */
  b_value= (*get_value_func)(thd, &b, &b_cache, *a, &is_null);
1025 1026
  if (is_null)
  {
1027 1028
    if (owner)
      owner->null_value= is_nulls_eq ? 0 : 1;
1029 1030 1031
    return is_nulls_eq ? 1 : -1;
  }

1032 1033
  if (owner)
    owner->null_value= 0;
1034 1035 1036 1037 1038 1039 1040 1041

  /* Compare values. */
  if (is_nulls_eq)
    return (a_value == b_value);
  return a_value < b_value ? -1 : (a_value > b_value ? 1 : 0);
}


1042
int Arg_comparator::compare_string()
unknown's avatar
unknown committed
1043 1044
{
  String *res1,*res2;
1045
  if ((res1= (*a)->val_str(&owner->tmp_value1)))
unknown's avatar
unknown committed
1046
  {
1047
    if ((res2= (*b)->val_str(&owner->tmp_value2)))
unknown's avatar
unknown committed
1048
    {
unknown's avatar
unknown committed
1049
      owner->null_value= 0;
1050
      return sortcmp(res1,res2,cmp_collation.collation);
unknown's avatar
unknown committed
1051 1052
    }
  }
unknown's avatar
unknown committed
1053
  owner->null_value= 1;
unknown's avatar
unknown committed
1054 1055 1056
  return -1;
}

unknown's avatar
unknown committed
1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089

/*
  Compare strings byte by byte. End spaces are also compared.

  RETURN
   < 0	*a < *b
   0	*b == *b
   > 0	*a > *b
*/

int Arg_comparator::compare_binary_string()
{
  String *res1,*res2;
  if ((res1= (*a)->val_str(&owner->tmp_value1)))
  {
    if ((res2= (*b)->val_str(&owner->tmp_value2)))
    {
      owner->null_value= 0;
      uint res1_length= res1->length();
      uint res2_length= res2->length();
      int cmp= memcmp(res1->ptr(), res2->ptr(), min(res1_length,res2_length));
      return cmp ? cmp : (int) (res1_length - res2_length);
    }
  }
  owner->null_value= 1;
  return -1;
}


/*
  Compare strings, but take into account that NULL == NULL
*/

unknown's avatar
unknown committed
1090 1091 1092
int Arg_comparator::compare_e_string()
{
  String *res1,*res2;
1093 1094
  res1= (*a)->val_str(&owner->tmp_value1);
  res2= (*b)->val_str(&owner->tmp_value2);
unknown's avatar
unknown committed
1095 1096
  if (!res1 || !res2)
    return test(res1 == res2);
1097
  return test(sortcmp(res1, res2, cmp_collation.collation) == 0);
unknown's avatar
unknown committed
1098 1099 1100
}


unknown's avatar
unknown committed
1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111
int Arg_comparator::compare_e_binary_string()
{
  String *res1,*res2;
  res1= (*a)->val_str(&owner->tmp_value1);
  res2= (*b)->val_str(&owner->tmp_value2);
  if (!res1 || !res2)
    return test(res1 == res2);
  return test(stringcmp(res1, res2) == 0);
}


1112
int Arg_comparator::compare_real()
unknown's avatar
unknown committed
1113
{
1114 1115 1116 1117 1118 1119
  /*
    Fix yet another manifestation of Bug#2338. 'Volatile' will instruct
    gcc to flush double values out of 80-bit Intel FPU registers before
    performing the comparison.
  */
  volatile double val1, val2;
unknown's avatar
Merge  
unknown committed
1120
  val1= (*a)->val_real();
1121
  if (!(*a)->null_value)
unknown's avatar
unknown committed
1122
  {
unknown's avatar
Merge  
unknown committed
1123
    val2= (*b)->val_real();
1124
    if (!(*b)->null_value)
unknown's avatar
unknown committed
1125
    {
unknown's avatar
unknown committed
1126
      owner->null_value= 0;
unknown's avatar
unknown committed
1127 1128 1129 1130 1131
      if (val1 < val2)	return -1;
      if (val1 == val2) return 0;
      return 1;
    }
  }
unknown's avatar
unknown committed
1132
  owner->null_value= 1;
unknown's avatar
unknown committed
1133 1134 1135
  return -1;
}

unknown's avatar
unknown committed
1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153
int Arg_comparator::compare_decimal()
{
  my_decimal value1;
  my_decimal *val1= (*a)->val_decimal(&value1);
  if (!(*a)->null_value)
  {
    my_decimal value2;
    my_decimal *val2= (*b)->val_decimal(&value2);
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
      return my_decimal_cmp(val1, val2);
    }
  }
  owner->null_value= 1;
  return -1;
}

unknown's avatar
unknown committed
1154 1155
int Arg_comparator::compare_e_real()
{
1156 1157
  double val1= (*a)->val_real();
  double val2= (*b)->val_real();
1158 1159
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
unknown's avatar
unknown committed
1160 1161
  return test(val1 == val2);
}
unknown's avatar
unknown committed
1162

unknown's avatar
unknown committed
1163 1164 1165 1166 1167 1168 1169 1170 1171 1172
int Arg_comparator::compare_e_decimal()
{
  my_decimal value1, value2;
  my_decimal *val1= (*a)->val_decimal(&value1);
  my_decimal *val2= (*b)->val_decimal(&value2);
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
  return test(my_decimal_cmp(val1, val2) == 0);
}

1173 1174 1175 1176 1177 1178 1179 1180 1181

int Arg_comparator::compare_real_fixed()
{
  /*
    Fix yet another manifestation of Bug#2338. 'Volatile' will instruct
    gcc to flush double values out of 80-bit Intel FPU registers before
    performing the comparison.
  */
  volatile double val1, val2;
unknown's avatar
unknown committed
1182
  val1= (*a)->val_real();
1183 1184
  if (!(*a)->null_value)
  {
unknown's avatar
unknown committed
1185
    val2= (*b)->val_real();
1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
      if (val1 == val2 || fabs(val1 - val2) < precision)
        return 0;
      if (val1 < val2)
        return -1;
      return 1;
    }
  }
  owner->null_value= 1;
  return -1;
}


int Arg_comparator::compare_e_real_fixed()
{
unknown's avatar
unknown committed
1203 1204
  double val1= (*a)->val_real();
  double val2= (*b)->val_real();
1205 1206 1207 1208 1209 1210
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
  return test(val1 == val2 || fabs(val1 - val2) < precision);
}


1211
int Arg_comparator::compare_int_signed()
unknown's avatar
unknown committed
1212
{
1213 1214
  longlong val1= (*a)->val_int();
  if (!(*a)->null_value)
unknown's avatar
unknown committed
1215
  {
1216 1217
    longlong val2= (*b)->val_int();
    if (!(*b)->null_value)
unknown's avatar
unknown committed
1218
    {
unknown's avatar
unknown committed
1219
      owner->null_value= 0;
unknown's avatar
unknown committed
1220 1221 1222 1223 1224
      if (val1 < val2)	return -1;
      if (val1 == val2)   return 0;
      return 1;
    }
  }
unknown's avatar
unknown committed
1225
  owner->null_value= 1;
unknown's avatar
unknown committed
1226 1227 1228
  return -1;
}

1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265

/*
  Compare values as BIGINT UNSIGNED.
*/

int Arg_comparator::compare_int_unsigned()
{
  ulonglong val1= (*a)->val_int();
  if (!(*a)->null_value)
  {
    ulonglong val2= (*b)->val_int();
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
      if (val1 < val2)	return -1;
      if (val1 == val2)   return 0;
      return 1;
    }
  }
  owner->null_value= 1;
  return -1;
}


/*
  Compare signed (*a) with unsigned (*B)
*/

int Arg_comparator::compare_int_signed_unsigned()
{
  longlong sval1= (*a)->val_int();
  if (!(*a)->null_value)
  {
    ulonglong uval2= (ulonglong)(*b)->val_int();
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
1266 1267 1268 1269 1270
      if (sval1 < 0 || (ulonglong)sval1 < uval2)
        return -1;
      if ((ulonglong)sval1 == uval2)
        return 0;
      return 1;
1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290
    }
  }
  owner->null_value= 1;
  return -1;
}


/*
  Compare unsigned (*a) with signed (*B)
*/

int Arg_comparator::compare_int_unsigned_signed()
{
  ulonglong uval1= (ulonglong)(*a)->val_int();
  if (!(*a)->null_value)
  {
    longlong sval2= (*b)->val_int();
    if (!(*b)->null_value)
    {
      owner->null_value= 0;
1291 1292 1293 1294 1295 1296 1297
      if (sval2 < 0)
        return 1;
      if (uval1 < (ulonglong)sval2)
        return -1;
      if (uval1 == (ulonglong)sval2)
        return 0;
      return 1;
1298 1299 1300 1301 1302 1303 1304
    }
  }
  owner->null_value= 1;
  return -1;
}


unknown's avatar
unknown committed
1305 1306
int Arg_comparator::compare_e_int()
{
1307 1308 1309 1310
  longlong val1= (*a)->val_int();
  longlong val2= (*b)->val_int();
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
unknown's avatar
unknown committed
1311 1312 1313
  return test(val1 == val2);
}

1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324
/*
  Compare unsigned *a with signed *b or signed *a with unsigned *b.
*/
int Arg_comparator::compare_e_int_diff_signedness()
{
  longlong val1= (*a)->val_int();
  longlong val2= (*b)->val_int();
  if ((*a)->null_value || (*b)->null_value)
    return test((*a)->null_value && (*b)->null_value);
  return (val1 >= 0) && test(val1 == val2);
}
unknown's avatar
unknown committed
1325

1326
int Arg_comparator::compare_row()
unknown's avatar
unknown committed
1327 1328
{
  int res= 0;
1329
  bool was_null= 0;
1330 1331
  (*a)->bring_value();
  (*b)->bring_value();
1332
  uint n= (*a)->cols();
unknown's avatar
unknown committed
1333
  for (uint i= 0; i<n; i++)
unknown's avatar
unknown committed
1334
  {
1335
    res= comparators[i].compare();
unknown's avatar
unknown committed
1336
    if (owner->null_value)
1337 1338
    {
      // NULL was compared
1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350
      switch (owner->functype()) {
      case Item_func::NE_FUNC:
        break; // NE never aborts on NULL even if abort_on_null is set
      case Item_func::LT_FUNC:
      case Item_func::LE_FUNC:
      case Item_func::GT_FUNC:
      case Item_func::GE_FUNC:
        return -1; // <, <=, > and >= always fail on NULL
      default: // EQ_FUNC
        if (owner->abort_on_null)
          return -1; // We do not need correct NULL returning
      }
1351 1352 1353 1354
      was_null= 1;
      owner->null_value= 0;
      res= 0;  // continue comparison (maybe we will meet explicit difference)
    }
1355
    else if (res)
1356
      return res;
unknown's avatar
unknown committed
1357
  }
1358 1359 1360
  if (was_null)
  {
    /*
1361 1362
      There was NULL(s) in comparison in some parts, but there was no
      explicit difference in other parts, so we have to return NULL.
1363 1364 1365 1366 1367
    */
    owner->null_value= 1;
    return -1;
  }
  return 0;
unknown's avatar
unknown committed
1368
}
unknown's avatar
unknown committed
1369

1370

unknown's avatar
unknown committed
1371 1372
int Arg_comparator::compare_e_row()
{
1373 1374
  (*a)->bring_value();
  (*b)->bring_value();
1375
  uint n= (*a)->cols();
unknown's avatar
unknown committed
1376 1377
  for (uint i= 0; i<n; i++)
  {
unknown's avatar
unknown committed
1378
    if (!comparators[i].compare())
1379
      return 0;
unknown's avatar
unknown committed
1380 1381 1382 1383
  }
  return 1;
}

1384

1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437
void Item_func_truth::fix_length_and_dec()
{
  maybe_null= 0;
  null_value= 0;
  decimals= 0;
  max_length= 1;
}


void Item_func_truth::print(String *str)
{
  str->append('(');
  args[0]->print(str);
  str->append(STRING_WITH_LEN(" is "));
  if (! affirmative)
    str->append(STRING_WITH_LEN("not "));
  if (value)
    str->append(STRING_WITH_LEN("true"));
  else
    str->append(STRING_WITH_LEN("false"));
  str->append(')');
}


bool Item_func_truth::val_bool()
{
  bool val= args[0]->val_bool();
  if (args[0]->null_value)
  {
    /*
      NULL val IS {TRUE, FALSE} --> FALSE
      NULL val IS NOT {TRUE, FALSE} --> TRUE
    */
    return (! affirmative);
  }

  if (affirmative)
  {
    /* {TRUE, FALSE} val IS {TRUE, FALSE} value */
    return (val == value);
  }

  /* {TRUE, FALSE} val IS NOT {TRUE, FALSE} value */
  return (val != value);
}


longlong Item_func_truth::val_int()
{
  return (val_bool() ? 1 : 0);
}


1438
bool Item_in_optimizer::fix_left(THD *thd, Item **ref)
unknown's avatar
unknown committed
1439
{
1440
  if (!args[0]->fixed && args[0]->fix_fields(thd, args) ||
1441
      !cache && !(cache= Item_cache::get_cache(args[0])))
1442
    return 1;
1443

1444
  cache->setup(args[0]);
1445
  if (cache->cols() == 1)
1446
  {
unknown's avatar
unknown committed
1447
    if ((used_tables_cache= args[0]->used_tables()))
unknown's avatar
unknown committed
1448
      cache->set_used_tables(OUTER_REF_TABLE_BIT);
1449 1450 1451
    else
      cache->set_used_tables(0);
  }
1452 1453 1454 1455
  else
  {
    uint n= cache->cols();
    for (uint i= 0; i < n; i++)
1456
    {
1457 1458
      if (args[0]->element_index(i)->used_tables())
	((Item_cache *)cache->element_index(i))->set_used_tables(OUTER_REF_TABLE_BIT);
1459
      else
1460
	((Item_cache *)cache->element_index(i))->set_used_tables(0);
1461
    }
unknown's avatar
unknown committed
1462
    used_tables_cache= args[0]->used_tables();
1463
  }
unknown's avatar
unknown committed
1464 1465
  not_null_tables_cache= args[0]->not_null_tables();
  with_sum_func= args[0]->with_sum_func;
1466 1467
  if ((const_item_cache= args[0]->const_item()))
    cache->store(args[0]);
1468 1469 1470 1471
  return 0;
}


1472
bool Item_in_optimizer::fix_fields(THD *thd, Item **ref)
1473
{
1474
  DBUG_ASSERT(fixed == 0);
1475
  if (fix_left(thd, ref))
unknown's avatar
unknown committed
1476
    return TRUE;
1477 1478 1479
  if (args[0]->maybe_null)
    maybe_null=1;

1480
  if (!args[1]->fixed && args[1]->fix_fields(thd, args+1))
unknown's avatar
unknown committed
1481
    return TRUE;
unknown's avatar
unknown committed
1482 1483 1484
  Item_in_subselect * sub= (Item_in_subselect *)args[1];
  if (args[0]->cols() != sub->engine->cols())
  {
unknown's avatar
unknown committed
1485
    my_error(ER_OPERAND_COLUMNS, MYF(0), args[0]->cols());
unknown's avatar
unknown committed
1486
    return TRUE;
unknown's avatar
unknown committed
1487
  }
1488 1489 1490 1491
  if (args[1]->maybe_null)
    maybe_null=1;
  with_sum_func= with_sum_func || args[1]->with_sum_func;
  used_tables_cache|= args[1]->used_tables();
unknown's avatar
unknown committed
1492
  not_null_tables_cache|= args[1]->not_null_tables();
1493
  const_item_cache&= args[1]->const_item();
1494
  fixed= 1;
unknown's avatar
unknown committed
1495
  return FALSE;
1496 1497
}

1498

1499 1500
longlong Item_in_optimizer::val_int()
{
unknown's avatar
unknown committed
1501
  bool tmp;
1502
  DBUG_ASSERT(fixed == 1);
1503
  cache->store(args[0]);
1504
  
1505
  if (cache->null_value)
1506
  {
1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531
    if (((Item_in_subselect*)args[1])->is_top_level_item())
    {
      /*
        We're evaluating "NULL IN (SELECT ...)". The result can be NULL or
        FALSE, and we can return one instead of another. Just return NULL.
      */
      null_value= 1;
    }
    else
    {
      if (!((Item_in_subselect*)args[1])->is_correlated &&
          result_for_null_param != UNKNOWN)
      {
        /* Use cached value from previous execution */
        null_value= result_for_null_param;
      }
      else
      {
        /*
          We're evaluating "NULL IN (SELECT ...)". The result is:
             FALSE if SELECT produces an empty set, or
             NULL  otherwise.
          We disable the predicates we've pushed down into subselect, run the
          subselect and see if it has produced any rows.
        */
1532 1533 1534 1535
        Item_in_subselect *item_subs=(Item_in_subselect*)args[1]; 
        if (cache->cols() == 1)
        {
          item_subs->set_cond_guard_var(0, FALSE);
1536
          (void) args[1]->val_bool_result();
1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549
          result_for_null_param= null_value= !item_subs->engine->no_rows();
          item_subs->set_cond_guard_var(0, TRUE);
        }
        else
        {
          uint i;
          uint ncols= cache->cols();
          /*
            Turn off the predicates that are based on column compares for
            which the left part is currently NULL
          */
          for (i= 0; i < ncols; i++)
          {
unknown's avatar
unknown committed
1550
            if (cache->element_index(i)->null_value)
1551 1552 1553
              item_subs->set_cond_guard_var(i, FALSE);
          }
          
1554
          (void) args[1]->val_bool_result();
1555 1556 1557 1558 1559 1560
          result_for_null_param= null_value= !item_subs->engine->no_rows();
          
          /* Turn all predicates back on */
          for (i= 0; i < ncols; i++)
            item_subs->set_cond_guard_var(i, TRUE);
        }
1561 1562
      }
    }
1563 1564
    return 0;
  }
unknown's avatar
unknown committed
1565
  tmp= args[1]->val_bool_result();
unknown's avatar
unknown committed
1566
  null_value= args[1]->null_value;
1567 1568 1569
  return tmp;
}

1570 1571 1572 1573 1574 1575 1576 1577

void Item_in_optimizer::keep_top_level_cache()
{
  cache->keep_array();
  save_cache= 1;
}


unknown's avatar
unknown committed
1578 1579 1580 1581
void Item_in_optimizer::cleanup()
{
  DBUG_ENTER("Item_in_optimizer::cleanup");
  Item_bool_func::cleanup();
1582 1583
  if (!save_cache)
    cache= 0;
unknown's avatar
unknown committed
1584 1585 1586
  DBUG_VOID_RETURN;
}

1587

1588
bool Item_in_optimizer::is_null()
1589
{
1590 1591
  cache->store(args[0]);
  return (null_value= (cache->null_value || args[1]->is_null()));
1592
}
unknown's avatar
unknown committed
1593

1594

unknown's avatar
unknown committed
1595 1596
longlong Item_func_eq::val_int()
{
1597
  DBUG_ASSERT(fixed == 1);
1598
  int value= cmp.compare();
unknown's avatar
unknown committed
1599 1600 1601
  return value == 0 ? 1 : 0;
}

1602

unknown's avatar
unknown committed
1603 1604
/* Same as Item_func_eq, but NULL = NULL */

unknown's avatar
unknown committed
1605 1606 1607 1608 1609 1610
void Item_func_equal::fix_length_and_dec()
{
  Item_bool_func2::fix_length_and_dec();
  maybe_null=null_value=0;
}

unknown's avatar
unknown committed
1611 1612
longlong Item_func_equal::val_int()
{
1613
  DBUG_ASSERT(fixed == 1);
1614
  return cmp.compare();
unknown's avatar
unknown committed
1615 1616 1617 1618
}

longlong Item_func_ne::val_int()
{
1619
  DBUG_ASSERT(fixed == 1);
1620
  int value= cmp.compare();
1621
  return value != 0 && !null_value ? 1 : 0;
unknown's avatar
unknown committed
1622 1623 1624 1625 1626
}


longlong Item_func_ge::val_int()
{
1627
  DBUG_ASSERT(fixed == 1);
1628
  int value= cmp.compare();
unknown's avatar
unknown committed
1629 1630 1631 1632 1633 1634
  return value >= 0 ? 1 : 0;
}


longlong Item_func_gt::val_int()
{
1635
  DBUG_ASSERT(fixed == 1);
1636
  int value= cmp.compare();
unknown's avatar
unknown committed
1637 1638 1639 1640 1641
  return value > 0 ? 1 : 0;
}

longlong Item_func_le::val_int()
{
1642
  DBUG_ASSERT(fixed == 1);
1643
  int value= cmp.compare();
unknown's avatar
unknown committed
1644 1645 1646 1647 1648 1649
  return value <= 0 && !null_value ? 1 : 0;
}


longlong Item_func_lt::val_int()
{
1650
  DBUG_ASSERT(fixed == 1);
1651
  int value= cmp.compare();
unknown's avatar
unknown committed
1652 1653 1654 1655 1656 1657
  return value < 0 && !null_value ? 1 : 0;
}


longlong Item_func_strcmp::val_int()
{
1658
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
1659 1660 1661 1662 1663 1664 1665
  String *a=args[0]->val_str(&tmp_value1);
  String *b=args[1]->val_str(&tmp_value2);
  if (!a || !b)
  {
    null_value=1;
    return 0;
  }
1666
  int value= sortcmp(a,b,cmp.cmp_collation.collation);
unknown's avatar
unknown committed
1667 1668 1669 1670 1671
  null_value=0;
  return !value ? 0 : (value < 0 ? (longlong) -1 : (longlong) 1);
}


1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691
bool Item_func_opt_neg::eq(const Item *item, bool binary_cmp) const
{
  /* Assume we don't have rtti */
  if (this == item)
    return 1;
  if (item->type() != FUNC_ITEM)
    return 0;
  Item_func *item_func=(Item_func*) item;
  if (arg_count != item_func->arg_count ||
      functype() != item_func->functype())
    return 0;
  if (negated != ((Item_func_opt_neg *) item_func)->negated)
    return 0;
  for (uint i=0; i < arg_count ; i++)
    if (!args[i]->eq(item_func->arguments()[i], binary_cmp))
      return 0;
  return 1;
}


unknown's avatar
unknown committed
1692 1693
void Item_func_interval::fix_length_and_dec()
{
unknown's avatar
unknown committed
1694 1695 1696 1697
  use_decimal_comparison= ((row->element_index(0)->result_type() ==
                            DECIMAL_RESULT) ||
                           (row->element_index(0)->result_type() ==
                            INT_RESULT));
1698
  if (row->cols() > 8)
unknown's avatar
unknown committed
1699
  {
1700 1701 1702
    bool consts=1;

    for (uint i=1 ; consts && i < row->cols() ; i++)
unknown's avatar
unknown committed
1703
    {
1704
      consts&= row->element_index(i)->const_item();
unknown's avatar
unknown committed
1705
    }
1706 1707

    if (consts &&
unknown's avatar
unknown committed
1708 1709
        (intervals=
          (interval_range*) sql_alloc(sizeof(interval_range)*(row->cols()-1))))
unknown's avatar
unknown committed
1710
    {
unknown's avatar
unknown committed
1711 1712 1713 1714
      if (use_decimal_comparison)
      {
        for (uint i=1 ; i < row->cols(); i++)
        {
1715
          Item *el= row->element_index(i);
unknown's avatar
unknown committed
1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739
          interval_range *range= intervals + (i-1);
          if ((el->result_type() == DECIMAL_RESULT) ||
              (el->result_type() == INT_RESULT))
          {
            range->type= DECIMAL_RESULT;
            range->dec.init();
            my_decimal *dec= el->val_decimal(&range->dec);
            if (dec != &range->dec)
            {
              range->dec= *dec;
              range->dec.fix_buffer_pointer();
            }
          }
          else
          {
            range->type= REAL_RESULT;
            range->dbl= el->val_real();
          }
        }
      }
      else
      {
        for (uint i=1 ; i < row->cols(); i++)
        {
1740
          intervals[i-1].dbl= row->element_index(i)->val_real();
unknown's avatar
unknown committed
1741 1742
        }
      }
unknown's avatar
unknown committed
1743 1744
    }
  }
unknown's avatar
unknown committed
1745 1746
  maybe_null= 0;
  max_length= 2;
1747
  used_tables_cache|= row->used_tables();
unknown's avatar
unknown committed
1748
  not_null_tables_cache= row->not_null_tables();
1749
  with_sum_func= with_sum_func || row->with_sum_func;
unknown's avatar
unknown committed
1750
  const_item_cache&= row->const_item();
unknown's avatar
unknown committed
1751 1752
}

unknown's avatar
unknown committed
1753

unknown's avatar
unknown committed
1754
/*
unknown's avatar
unknown committed
1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768
  Execute Item_func_interval()

  SYNOPSIS
    Item_func_interval::val_int()

  NOTES
    If we are doing a decimal comparison, we are
    evaluating the first item twice.

  RETURN
    -1 if null value,
    0 if lower than lowest
    1 - arg_count-1 if between args[n] and args[n+1]
    arg_count if higher than biggest argument
unknown's avatar
unknown committed
1769 1770 1771 1772
*/

longlong Item_func_interval::val_int()
{
1773
  DBUG_ASSERT(fixed == 1);
1774
  double value;
unknown's avatar
unknown committed
1775
  my_decimal dec_buf, *dec= NULL;
unknown's avatar
unknown committed
1776 1777
  uint i;

unknown's avatar
unknown committed
1778 1779
  if (use_decimal_comparison)
  {
1780 1781
    dec= row->element_index(0)->val_decimal(&dec_buf);
    if (row->element_index(0)->null_value)
1782 1783 1784 1785 1786
      return -1;
    my_decimal2double(E_DEC_FATAL_ERROR, dec, &value);
  }
  else
  {
1787 1788
    value= row->element_index(0)->val_real();
    if (row->element_index(0)->null_value)
1789
      return -1;
unknown's avatar
unknown committed
1790
  }
unknown's avatar
unknown committed
1791

unknown's avatar
unknown committed
1792 1793 1794
  if (intervals)
  {					// Use binary search to find interval
    uint start,end;
1795
    start= 0;
unknown's avatar
unknown committed
1796
    end=   row->cols()-2;
unknown's avatar
unknown committed
1797 1798
    while (start != end)
    {
unknown's avatar
unknown committed
1799
      uint mid= (start + end + 1) / 2;
unknown's avatar
unknown committed
1800 1801
      interval_range *range= intervals + mid;
      my_bool cmp_result;
unknown's avatar
unknown committed
1802 1803 1804 1805 1806
      /*
        The values in the range intervall may have different types,
        Only do a decimal comparision of the first argument is a decimal
        and we are comparing against a decimal
      */
unknown's avatar
unknown committed
1807 1808 1809 1810 1811
      if (dec && range->type == DECIMAL_RESULT)
        cmp_result= my_decimal_cmp(&range->dec, dec) <= 0;
      else
        cmp_result= (range->dbl <= value);
      if (cmp_result)
unknown's avatar
unknown committed
1812
	start= mid;
unknown's avatar
unknown committed
1813
      else
unknown's avatar
unknown committed
1814
	end= mid - 1;
unknown's avatar
unknown committed
1815
    }
unknown's avatar
unknown committed
1816 1817
    interval_range *range= intervals+start;
    return ((dec && range->type == DECIMAL_RESULT) ?
unknown's avatar
unknown committed
1818
            my_decimal_cmp(dec, &range->dec) < 0 :
unknown's avatar
unknown committed
1819
            value < range->dbl) ? 0 : start + 1;
unknown's avatar
unknown committed
1820
  }
1821 1822

  for (i=1 ; i < row->cols() ; i++)
unknown's avatar
unknown committed
1823
  {
1824
    Item *el= row->element_index(i);
unknown's avatar
unknown committed
1825 1826 1827 1828
    if (use_decimal_comparison &&
        ((el->result_type() == DECIMAL_RESULT) ||
         (el->result_type() == INT_RESULT)))
    {
1829
      my_decimal e_dec_buf, *e_dec= row->element_index(i)->val_decimal(&e_dec_buf);
unknown's avatar
unknown committed
1830 1831 1832
      if (my_decimal_cmp(e_dec, dec) > 0)
        return i-1;
    }
1833
    else if (row->element_index(i)->val_real() > value)
unknown's avatar
unknown committed
1834
      return i-1;
unknown's avatar
unknown committed
1835
  }
1836
  return i-1;
unknown's avatar
unknown committed
1837 1838
}

unknown's avatar
unknown committed
1839

unknown's avatar
unknown committed
1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868
/*
  Perform context analysis of a BETWEEN item tree

  SYNOPSIS:
    fix_fields()
    thd     reference to the global context of the query thread
    tables  list of all open tables involved in the query
    ref     pointer to Item* variable where pointer to resulting "fixed"
            item is to be assigned

  DESCRIPTION
    This function performs context analysis (name resolution) and calculates
    various attributes of the item tree with Item_func_between as its root.
    The function saves in ref the pointer to the item or to a newly created
    item that is considered as a replacement for the original one.

  NOTES
    Let T0(e)/T1(e) be the value of not_null_tables(e) when e is used on
    a predicate/function level. Then it's easy to show that:
      T0(e BETWEEN e1 AND e2)     = union(T1(e),T1(e1),T1(e2))
      T1(e BETWEEN e1 AND e2)     = union(T1(e),intersection(T1(e1),T1(e2)))
      T0(e NOT BETWEEN e1 AND e2) = union(T1(e),intersection(T1(e1),T1(e2)))
      T1(e NOT BETWEEN e1 AND e2) = union(T1(e),intersection(T1(e1),T1(e2)))

  RETURN
    0   ok
    1   got error
*/

unknown's avatar
unknown committed
1869
bool Item_func_between::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
1870
{
1871
  if (Item_func_opt_neg::fix_fields(thd, ref))
unknown's avatar
unknown committed
1872 1873
    return 1;

1874 1875
  thd->lex->current_select->between_count++;

unknown's avatar
unknown committed
1876 1877 1878 1879 1880
  /* not_null_tables_cache == union(T1(e),T1(e1),T1(e2)) */
  if (pred_level && !negated)
    return 0;

  /* not_null_tables_cache == union(T1(e), intersection(T1(e1),T1(e2))) */
unknown's avatar
unknown committed
1881 1882 1883
  not_null_tables_cache= (args[0]->not_null_tables() |
                          (args[1]->not_null_tables() &
                           args[2]->not_null_tables()));
unknown's avatar
unknown committed
1884 1885 1886 1887 1888

  return 0;
}


unknown's avatar
unknown committed
1889 1890
void Item_func_between::fix_length_and_dec()
{
1891 1892 1893
  max_length= 1;
  int i;
  bool datetime_found= FALSE;
1894
  int time_items_found= 0;
1895
  compare_as_dates= TRUE;
1896
  THD *thd= current_thd;
unknown's avatar
unknown committed
1897

1898 1899
  /*
    As some compare functions are generated after sql_yacc,
unknown's avatar
unknown committed
1900
    we have to check for out of memory conditions here
1901
  */
unknown's avatar
unknown committed
1902 1903
  if (!args[0] || !args[1] || !args[2])
    return;
1904
  if ( agg_cmp_type(&cmp_type, args, 3))
1905
    return;
unknown's avatar
unknown committed
1906
  if (cmp_type == STRING_RESULT &&
1907
      agg_arg_charsets(cmp_collation, args, 3, MY_COLL_CMP_CONV, 1))
unknown's avatar
unknown committed
1908
   return;
1909

unknown's avatar
unknown committed
1910
  /*
1911 1912 1913
    Detect the comparison of DATE/DATETIME items.
    At least one of items should be a DATE/DATETIME item and other items
    should return the STRING result.
unknown's avatar
unknown committed
1914
  */
1915
  if (cmp_type == STRING_RESULT)
unknown's avatar
unknown committed
1916
  {
1917
    for (i= 0; i < 3; i++)
unknown's avatar
unknown committed
1918
    {
1919 1920 1921 1922 1923 1924 1925 1926
      if (args[i]->is_datetime())
      {
        datetime_found= TRUE;
        continue;
      }
      if (args[i]->field_type() == MYSQL_TYPE_TIME &&
          args[i]->result_as_longlong())
        time_items_found++;
unknown's avatar
unknown committed
1927
    }
1928 1929 1930 1931 1932 1933 1934 1935
  }
  if (!datetime_found)
    compare_as_dates= FALSE;

  if (compare_as_dates)
  {
    ge_cmp.set_datetime_cmp_func(args, args + 1);
    le_cmp.set_datetime_cmp_func(args, args + 2);
unknown's avatar
unknown committed
1936
  }
1937 1938 1939 1940 1941
  else if (time_items_found == 3)
  {
    /* Compare TIME items as integers. */
    cmp_type= INT_RESULT;
  }
1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958
  else if (args[0]->real_item()->type() == FIELD_ITEM &&
           thd->lex->sql_command != SQLCOM_CREATE_VIEW &&
           thd->lex->sql_command != SQLCOM_SHOW_CREATE)
  {
    Field *field=((Item_field*) (args[0]->real_item()))->field;
    if (field->can_be_compared_as_longlong())
    {
      /*
        The following can't be recoded with || as convert_constant_item
        changes the argument
      */
      if (convert_constant_item(thd, field,&args[1]))
        cmp_type=INT_RESULT;			// Works for all types.
      if (convert_constant_item(thd, field,&args[2]))
        cmp_type=INT_RESULT;			// Works for all types.
    }
  }
unknown's avatar
unknown committed
1959 1960 1961 1962 1963
}


longlong Item_func_between::val_int()
{						// ANSI BETWEEN
1964
  DBUG_ASSERT(fixed == 1);
1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
  if (compare_as_dates)
  {
    int ge_res, le_res;

    ge_res= ge_cmp.compare();
    if ((null_value= args[0]->null_value))
      return 0;
    le_res= le_cmp.compare();

    if (!args[1]->null_value && !args[2]->null_value)
      return (longlong) ((ge_res >= 0 && le_res <=0) != negated);
    else if (args[1]->null_value)
    {
      null_value= le_res > 0;			// not null if false range.
    }
    else
    {
      null_value= ge_res < 0;
    }
  }
  else if (cmp_type == STRING_RESULT)
unknown's avatar
unknown committed
1986 1987 1988 1989 1990 1991 1992 1993
  {
    String *value,*a,*b;
    value=args[0]->val_str(&value0);
    if ((null_value=args[0]->null_value))
      return 0;
    a=args[1]->val_str(&value1);
    b=args[2]->val_str(&value2);
    if (!args[1]->null_value && !args[2]->null_value)
unknown's avatar
unknown committed
1994 1995 1996
      return (longlong) ((sortcmp(value,a,cmp_collation.collation) >= 0 &&
                          sortcmp(value,b,cmp_collation.collation) <= 0) !=
                         negated);
unknown's avatar
unknown committed
1997 1998 1999 2000
    if (args[1]->null_value && args[2]->null_value)
      null_value=1;
    else if (args[1]->null_value)
    {
unknown's avatar
unknown committed
2001 2002
      // Set to not null if false range.
      null_value= sortcmp(value,b,cmp_collation.collation) <= 0;
unknown's avatar
unknown committed
2003 2004 2005
    }
    else
    {
unknown's avatar
unknown committed
2006 2007
      // Set to not null if false range.
      null_value= sortcmp(value,a,cmp_collation.collation) >= 0;
unknown's avatar
unknown committed
2008 2009 2010 2011
    }
  }
  else if (cmp_type == INT_RESULT)
  {
2012
    longlong value=args[0]->val_int(), a, b;
unknown's avatar
unknown committed
2013
    if ((null_value=args[0]->null_value))
2014
      return 0;					/* purecov: inspected */
unknown's avatar
unknown committed
2015 2016 2017
    a=args[1]->val_int();
    b=args[2]->val_int();
    if (!args[1]->null_value && !args[2]->null_value)
unknown's avatar
unknown committed
2018
      return (longlong) ((value >= a && value <= b) != negated);
unknown's avatar
unknown committed
2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029
    if (args[1]->null_value && args[2]->null_value)
      null_value=1;
    else if (args[1]->null_value)
    {
      null_value= value <= b;			// not null if false range.
    }
    else
    {
      null_value= value >= a;
    }
  }
unknown's avatar
unknown committed
2030 2031 2032 2033 2034 2035 2036 2037 2038
  else if (cmp_type == DECIMAL_RESULT)
  {
    my_decimal dec_buf, *dec= args[0]->val_decimal(&dec_buf),
               a_buf, *a_dec, b_buf, *b_dec;
    if ((null_value=args[0]->null_value))
      return 0;					/* purecov: inspected */
    a_dec= args[1]->val_decimal(&a_buf);
    b_dec= args[2]->val_decimal(&b_buf);
    if (!args[1]->null_value && !args[2]->null_value)
2039 2040
      return (longlong) ((my_decimal_cmp(dec, a_dec) >= 0 &&
                          my_decimal_cmp(dec, b_dec) <= 0) != negated);
unknown's avatar
unknown committed
2041 2042 2043 2044 2045 2046 2047
    if (args[1]->null_value && args[2]->null_value)
      null_value=1;
    else if (args[1]->null_value)
      null_value= (my_decimal_cmp(dec, b_dec) <= 0);
    else
      null_value= (my_decimal_cmp(dec, a_dec) >= 0);
  }
unknown's avatar
unknown committed
2048 2049
  else
  {
2050
    double value= args[0]->val_real(),a,b;
unknown's avatar
unknown committed
2051
    if ((null_value=args[0]->null_value))
2052
      return 0;					/* purecov: inspected */
2053 2054
    a= args[1]->val_real();
    b= args[2]->val_real();
unknown's avatar
unknown committed
2055
    if (!args[1]->null_value && !args[2]->null_value)
unknown's avatar
unknown committed
2056
      return (longlong) ((value >= a && value <= b) != negated);
unknown's avatar
unknown committed
2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067
    if (args[1]->null_value && args[2]->null_value)
      null_value=1;
    else if (args[1]->null_value)
    {
      null_value= value <= b;			// not null if false range.
    }
    else
    {
      null_value= value >= a;
    }
  }
unknown's avatar
unknown committed
2068
  return (longlong) (!null_value && negated);
unknown's avatar
unknown committed
2069 2070
}

2071 2072 2073 2074 2075

void Item_func_between::print(String *str)
{
  str->append('(');
  args[0]->print(str);
unknown's avatar
unknown committed
2076
  if (negated)
2077 2078
    str->append(STRING_WITH_LEN(" not"));
  str->append(STRING_WITH_LEN(" between "));
2079
  args[1]->print(str);
2080
  str->append(STRING_WITH_LEN(" and "));
2081 2082 2083 2084
  args[2]->print(str);
  str->append(')');
}

unknown's avatar
unknown committed
2085 2086 2087
void
Item_func_ifnull::fix_length_and_dec()
{
2088
  agg_result_type(&hybrid_type, args, 2);
unknown's avatar
unknown committed
2089
  maybe_null=args[1]->maybe_null;
unknown's avatar
unknown committed
2090
  decimals= max(args[0]->decimals, args[1]->decimals);
2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104
  unsigned_flag= args[0]->unsigned_flag && args[1]->unsigned_flag;

  if (hybrid_type == DECIMAL_RESULT || hybrid_type == INT_RESULT) 
  {
    int len0= args[0]->max_length - args[0]->decimals
      - (args[0]->unsigned_flag ? 0 : 1);

    int len1= args[1]->max_length - args[1]->decimals
      - (args[1]->unsigned_flag ? 0 : 1);

    max_length= max(len0, len1) + decimals + (unsigned_flag ? 0 : 1);
  }
  else
    max_length= max(args[0]->max_length, args[1]->max_length);
2105

unknown's avatar
unknown committed
2106
  switch (hybrid_type) {
unknown's avatar
unknown committed
2107
  case STRING_RESULT:
2108
    agg_arg_charsets(collation, args, arg_count, MY_COLL_CMP_CONV, 1);
unknown's avatar
unknown committed
2109 2110 2111 2112 2113
    break;
  case DECIMAL_RESULT:
  case REAL_RESULT:
    break;
  case INT_RESULT:
2114
    decimals= 0;
unknown's avatar
unknown committed
2115 2116 2117 2118 2119
    break;
  case ROW_RESULT:
  default:
    DBUG_ASSERT(0);
  }
2120
  cached_field_type= agg_field_type(args, 2);
unknown's avatar
unknown committed
2121 2122
}

unknown's avatar
unknown committed
2123 2124 2125 2126 2127 2128 2129 2130

uint Item_func_ifnull::decimal_precision() const
{
  int max_int_part=max(args[0]->decimal_int_part(),args[1]->decimal_int_part());
  return min(max_int_part + decimals, DECIMAL_MAX_PRECISION);
}


2131 2132 2133
enum_field_types Item_func_ifnull::field_type() const 
{
  return cached_field_type;
unknown's avatar
unknown committed
2134 2135
}

2136 2137
Field *Item_func_ifnull::tmp_table_field(TABLE *table)
{
unknown's avatar
unknown committed
2138
  return tmp_table_field_from_field_type(table, 0);
2139
}
2140

unknown's avatar
unknown committed
2141
double
unknown's avatar
unknown committed
2142
Item_func_ifnull::real_op()
unknown's avatar
unknown committed
2143
{
2144
  DBUG_ASSERT(fixed == 1);
2145
  double value= args[0]->val_real();
unknown's avatar
unknown committed
2146 2147 2148 2149 2150
  if (!args[0]->null_value)
  {
    null_value=0;
    return value;
  }
2151
  value= args[1]->val_real();
unknown's avatar
unknown committed
2152 2153 2154 2155 2156 2157
  if ((null_value=args[1]->null_value))
    return 0.0;
  return value;
}

longlong
unknown's avatar
unknown committed
2158
Item_func_ifnull::int_op()
unknown's avatar
unknown committed
2159
{
2160
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172
  longlong value=args[0]->val_int();
  if (!args[0]->null_value)
  {
    null_value=0;
    return value;
  }
  value=args[1]->val_int();
  if ((null_value=args[1]->null_value))
    return 0;
  return value;
}

unknown's avatar
unknown committed
2173

unknown's avatar
unknown committed
2174
my_decimal *Item_func_ifnull::decimal_op(my_decimal *decimal_value)
unknown's avatar
unknown committed
2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189
{
  DBUG_ASSERT(fixed == 1);
  my_decimal *value= args[0]->val_decimal(decimal_value);
  if (!args[0]->null_value)
  {
    null_value= 0;
    return value;
  }
  value= args[1]->val_decimal(decimal_value);
  if ((null_value= args[1]->null_value))
    return 0;
  return value;
}


unknown's avatar
unknown committed
2190
String *
unknown's avatar
unknown committed
2191
Item_func_ifnull::str_op(String *str)
unknown's avatar
unknown committed
2192
{
2193
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2194 2195 2196 2197
  String *res  =args[0]->val_str(str);
  if (!args[0]->null_value)
  {
    null_value=0;
2198
    res->set_charset(collation.collation);
unknown's avatar
unknown committed
2199 2200 2201 2202 2203
    return res;
  }
  res=args[1]->val_str(str);
  if ((null_value=args[1]->null_value))
    return 0;
2204
  res->set_charset(collation.collation);
unknown's avatar
unknown committed
2205 2206 2207
  return res;
}

2208

unknown's avatar
unknown committed
2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236
/*
  Perform context analysis of an IF item tree

  SYNOPSIS:
    fix_fields()
    thd     reference to the global context of the query thread
    tables  list of all open tables involved in the query
    ref     pointer to Item* variable where pointer to resulting "fixed"
            item is to be assigned

  DESCRIPTION
    This function performs context analysis (name resolution) and calculates
    various attributes of the item tree with Item_func_if as its root.
    The function saves in ref the pointer to the item or to a newly created
    item that is considered as a replacement for the original one.

  NOTES
    Let T0(e)/T1(e) be the value of not_null_tables(e) when e is used on
    a predicate/function level. Then it's easy to show that:
      T0(IF(e,e1,e2)  = T1(IF(e,e1,e2))
      T1(IF(e,e1,e2)) = intersection(T1(e1),T1(e2))

  RETURN
    0   ok
    1   got error
*/

bool
2237
Item_func_if::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
2238 2239 2240 2241
{
  DBUG_ASSERT(fixed == 0);
  args[0]->top_level_item();

2242
  if (Item_func::fix_fields(thd, ref))
unknown's avatar
unknown committed
2243 2244
    return 1;

unknown's avatar
unknown committed
2245 2246
  not_null_tables_cache= (args[1]->not_null_tables() &
                          args[2]->not_null_tables());
unknown's avatar
unknown committed
2247 2248 2249 2250 2251

  return 0;
}


unknown's avatar
unknown committed
2252 2253 2254 2255
void
Item_func_if::fix_length_and_dec()
{
  maybe_null=args[1]->maybe_null || args[2]->maybe_null;
unknown's avatar
unknown committed
2256
  decimals= max(args[1]->decimals, args[2]->decimals);
2257
  unsigned_flag=args[1]->unsigned_flag && args[2]->unsigned_flag;
2258

unknown's avatar
unknown committed
2259 2260
  enum Item_result arg1_type=args[1]->result_type();
  enum Item_result arg2_type=args[2]->result_type();
unknown's avatar
unknown committed
2261 2262
  bool null1=args[1]->const_item() && args[1]->null_value;
  bool null2=args[2]->const_item() && args[2]->null_value;
2263 2264 2265 2266

  if (null1)
  {
    cached_result_type= arg2_type;
2267
    collation.set(args[2]->collation.collation);
2268
    cached_field_type= args[2]->field_type();
2269 2270 2271
  }
  else if (null2)
  {
unknown's avatar
unknown committed
2272
    cached_result_type= arg1_type;
2273
    collation.set(args[1]->collation.collation);
2274
    cached_field_type= args[1]->field_type();
2275
  }
unknown's avatar
unknown committed
2276
  else
2277
  {
2278 2279 2280
    agg_result_type(&cached_result_type, args+1, 2);
    if (cached_result_type == STRING_RESULT)
    {
2281
      if (agg_arg_charsets(collation, args+1, 2, MY_COLL_ALLOW_CONV, 1))
2282
        return;
2283
    }
2284
    else
2285
    {
2286
      collation.set(&my_charset_bin);	// Number
2287
    }
2288
    cached_field_type= agg_field_type(args + 1, 2);
2289
  }
2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303

  if ((cached_result_type == DECIMAL_RESULT )
      || (cached_result_type == INT_RESULT))
  {
    int len1= args[1]->max_length - args[1]->decimals
      - (args[1]->unsigned_flag ? 0 : 1);

    int len2= args[2]->max_length - args[2]->decimals
      - (args[2]->unsigned_flag ? 0 : 1);

    max_length=max(len1, len2) + decimals + (unsigned_flag ? 0 : 1);
  }
  else
    max_length= max(args[1]->max_length, args[2]->max_length);
unknown's avatar
unknown committed
2304 2305 2306
}


unknown's avatar
unknown committed
2307 2308 2309 2310 2311 2312 2313 2314
uint Item_func_if::decimal_precision() const
{
  int precision=(max(args[1]->decimal_int_part(),args[2]->decimal_int_part())+
                 decimals);
  return min(precision, DECIMAL_MAX_PRECISION);
}


unknown's avatar
unknown committed
2315
double
2316
Item_func_if::val_real()
unknown's avatar
unknown committed
2317
{
2318
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2319
  Item *arg= args[0]->val_bool() ? args[1] : args[2];
2320
  double value= arg->val_real();
unknown's avatar
unknown committed
2321 2322 2323 2324 2325 2326 2327
  null_value=arg->null_value;
  return value;
}

longlong
Item_func_if::val_int()
{
2328
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2329
  Item *arg= args[0]->val_bool() ? args[1] : args[2];
unknown's avatar
unknown committed
2330 2331 2332 2333 2334 2335 2336 2337
  longlong value=arg->val_int();
  null_value=arg->null_value;
  return value;
}

String *
Item_func_if::val_str(String *str)
{
2338
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2339
  Item *arg= args[0]->val_bool() ? args[1] : args[2];
unknown's avatar
unknown committed
2340
  String *res=arg->val_str(str);
2341
  if (res)
2342
    res->set_charset(collation.collation);
unknown's avatar
unknown committed
2343 2344 2345 2346 2347
  null_value=arg->null_value;
  return res;
}


unknown's avatar
unknown committed
2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358
my_decimal *
Item_func_if::val_decimal(my_decimal *decimal_value)
{
  DBUG_ASSERT(fixed == 1);
  Item *arg= args[0]->val_bool() ? args[1] : args[2];
  my_decimal *value= arg->val_decimal(decimal_value);
  null_value= arg->null_value;
  return value;
}


unknown's avatar
unknown committed
2359 2360 2361 2362 2363 2364 2365 2366 2367
void
Item_func_nullif::fix_length_and_dec()
{
  Item_bool_func2::fix_length_and_dec();
  maybe_null=1;
  if (args[0])					// Only false if EOM
  {
    max_length=args[0]->max_length;
    decimals=args[0]->decimals;
unknown's avatar
unknown committed
2368 2369
    unsigned_flag= args[0]->unsigned_flag;
    cached_result_type= args[0]->result_type();
2370
    if (cached_result_type == STRING_RESULT &&
2371
        agg_arg_charsets(collation, args, arg_count, MY_COLL_CMP_CONV, 1))
2372
      return;
unknown's avatar
unknown committed
2373 2374 2375
  }
}

unknown's avatar
unknown committed
2376

unknown's avatar
unknown committed
2377
/*
2378
  nullif () returns NULL if arguments are equal, else it returns the
unknown's avatar
unknown committed
2379 2380 2381 2382 2383 2384
  first argument.
  Note that we have to evaluate the first argument twice as the compare
  may have been done with a different type than return value
*/

double
2385
Item_func_nullif::val_real()
unknown's avatar
unknown committed
2386
{
2387
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2388
  double value;
unknown's avatar
unknown committed
2389
  if (!cmp.compare())
unknown's avatar
unknown committed
2390 2391 2392 2393
  {
    null_value=1;
    return 0.0;
  }
2394
  value= args[0]->val_real();
unknown's avatar
unknown committed
2395 2396 2397 2398 2399 2400 2401
  null_value=args[0]->null_value;
  return value;
}

longlong
Item_func_nullif::val_int()
{
2402
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2403
  longlong value;
unknown's avatar
unknown committed
2404
  if (!cmp.compare())
unknown's avatar
unknown committed
2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416
  {
    null_value=1;
    return 0;
  }
  value=args[0]->val_int();
  null_value=args[0]->null_value;
  return value;
}

String *
Item_func_nullif::val_str(String *str)
{
2417
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2418
  String *res;
unknown's avatar
unknown committed
2419
  if (!cmp.compare())
unknown's avatar
unknown committed
2420 2421 2422 2423 2424 2425 2426 2427 2428
  {
    null_value=1;
    return 0;
  }
  res=args[0]->val_str(str);
  null_value=args[0]->null_value;
  return res;
}

2429

unknown's avatar
unknown committed
2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445
my_decimal *
Item_func_nullif::val_decimal(my_decimal * decimal_value)
{
  DBUG_ASSERT(fixed == 1);
  my_decimal *res;
  if (!cmp.compare())
  {
    null_value=1;
    return 0;
  }
  res= args[0]->val_decimal(decimal_value);
  null_value= args[0]->null_value;
  return res;
}


2446 2447 2448
bool
Item_func_nullif::is_null()
{
unknown's avatar
unknown committed
2449
  return (null_value= (!cmp.compare() ? 1 : args[0]->null_value)); 
2450 2451
}

2452

unknown's avatar
unknown committed
2453
/*
2454
  Return the matching ITEM or NULL if all compares (including else) failed
2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477

  SYNOPSIS
    find_item()
      str      Buffer string

  DESCRIPTION
    Find and return matching items for CASE or ELSE item if all compares
    are failed or NULL if ELSE item isn't defined.

  IMPLEMENTATION
    In order to do correct comparisons of the CASE expression (the expression
    between CASE and the first WHEN) with each WHEN expression several
    comparators are used. One for each result type. CASE expression can be
    evaluated up to # of different result types are used. To check whether
    the CASE expression already was evaluated for a particular result type
    a bit mapped variable value_added_map is used. Result types are mapped
    to it according to their int values i.e. STRING_RESULT is mapped to bit
    0, REAL_RESULT to bit 1, so on.

  RETURN
    NULL - Nothing found and there is no ELSE expression defined
    item - Found item or ELSE item if defined and all comparisons are
           failed
unknown's avatar
unknown committed
2478 2479 2480 2481
*/

Item *Item_func_case::find_item(String *str)
{
2482
  uint value_added_map= 0;
unknown's avatar
unknown committed
2483

2484
  if (first_expr_num == -1)
unknown's avatar
unknown committed
2485
  {
2486
    for (uint i=0 ; i < ncases ; i+=2)
unknown's avatar
unknown committed
2487
    {
unknown's avatar
unknown committed
2488
      // No expression between CASE and the first WHEN
unknown's avatar
unknown committed
2489
      if (args[i]->val_bool())
unknown's avatar
unknown committed
2490 2491 2492
	return args[i+1];
      continue;
    }
2493 2494 2495 2496 2497
  }
  else
  {
    /* Compare every WHEN argument with it and return the first match */
    for (uint i=0 ; i < ncases ; i+=2)
unknown's avatar
unknown committed
2498
    {
2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510
      cmp_type= item_cmp_type(left_result_type, args[i]->result_type());
      DBUG_ASSERT(cmp_type != ROW_RESULT);
      DBUG_ASSERT(cmp_items[(uint)cmp_type]);
      if (!(value_added_map & (1<<(uint)cmp_type)))
      {
        cmp_items[(uint)cmp_type]->store_value(args[first_expr_num]);
        if ((null_value=args[first_expr_num]->null_value))
          return else_expr_num != -1 ? args[else_expr_num] : 0;
        value_added_map|= 1<<(uint)cmp_type;
      }
      if (!cmp_items[(uint)cmp_type]->cmp(args[i]) && !args[i]->null_value)
        return args[i + 1];
unknown's avatar
unknown committed
2511 2512 2513
    }
  }
  // No, WHEN clauses all missed, return ELSE expression
2514
  return else_expr_num != -1 ? args[else_expr_num] : 0;
unknown's avatar
unknown committed
2515 2516 2517 2518 2519
}


String *Item_func_case::val_str(String *str)
{
2520
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2521 2522 2523 2524 2525 2526 2527 2528
  String *res;
  Item *item=find_item(str);

  if (!item)
  {
    null_value=1;
    return 0;
  }
unknown's avatar
unknown committed
2529
  null_value= 0;
unknown's avatar
unknown committed
2530
  if (!(res=item->val_str(str)))
unknown's avatar
unknown committed
2531
    null_value= 1;
unknown's avatar
unknown committed
2532 2533 2534 2535 2536 2537
  return res;
}


longlong Item_func_case::val_int()
{
2538
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2539
  char buff[MAX_FIELD_WIDTH];
2540
  String dummy_str(buff,sizeof(buff),default_charset());
unknown's avatar
unknown committed
2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553
  Item *item=find_item(&dummy_str);
  longlong res;

  if (!item)
  {
    null_value=1;
    return 0;
  }
  res=item->val_int();
  null_value=item->null_value;
  return res;
}

2554
double Item_func_case::val_real()
unknown's avatar
unknown committed
2555
{
2556
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2557
  char buff[MAX_FIELD_WIDTH];
2558
  String dummy_str(buff,sizeof(buff),default_charset());
unknown's avatar
unknown committed
2559 2560 2561 2562 2563 2564 2565 2566
  Item *item=find_item(&dummy_str);
  double res;

  if (!item)
  {
    null_value=1;
    return 0;
  }
2567
  res= item->val_real();
unknown's avatar
unknown committed
2568 2569 2570 2571
  null_value=item->null_value;
  return res;
}

unknown's avatar
unknown committed
2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592

my_decimal *Item_func_case::val_decimal(my_decimal *decimal_value)
{
  DBUG_ASSERT(fixed == 1);
  char buff[MAX_FIELD_WIDTH];
  String dummy_str(buff, sizeof(buff), default_charset());
  Item *item= find_item(&dummy_str);
  my_decimal *res;

  if (!item)
  {
    null_value=1;
    return 0;
  }

  res= item->val_decimal(decimal_value);
  null_value= item->null_value;
  return res;
}


unknown's avatar
unknown committed
2593
bool Item_func_case::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
2594 2595 2596 2597 2598
{
  /*
    buff should match stack usage from
    Item_func_case::val_int() -> Item_func_case::find_item()
  */
2599
#ifndef EMBEDDED_LIBRARY
2600
  uchar buff[MAX_FIELD_WIDTH*2+sizeof(String)*2+sizeof(String*)*2+sizeof(double)*2+sizeof(longlong)*2];
2601
#endif
unknown's avatar
unknown committed
2602 2603 2604 2605 2606
  bool res= Item_func::fix_fields(thd, ref);
  /*
    Call check_stack_overrun after fix_fields to be sure that stack variable
    is not optimized away
  */
unknown's avatar
unknown committed
2607 2608
  if (check_stack_overrun(thd, STACK_MIN_SIZE, buff))
    return TRUE;				// Fatal error flag is set!
unknown's avatar
unknown committed
2609
  return res;
unknown's avatar
unknown committed
2610 2611 2612 2613
}



unknown's avatar
unknown committed
2614
void Item_func_case::fix_length_and_dec()
2615
{
2616 2617
  Item **agg;
  uint nagg;
2618
  uint found_types= 0;
2619 2620 2621
  if (!(agg= (Item**) sql_alloc(sizeof(Item*)*(ncases+1))))
    return;
  
2622 2623 2624 2625
  /*
    Aggregate all THEN and ELSE expression types
    and collations when string result
  */
2626 2627 2628 2629 2630 2631 2632 2633 2634
  
  for (nagg= 0 ; nagg < ncases/2 ; nagg++)
    agg[nagg]= args[nagg*2+1];
  
  if (else_expr_num != -1)
    agg[nagg++]= args[else_expr_num];
  
  agg_result_type(&cached_result_type, agg, nagg);
  if ((cached_result_type == STRING_RESULT) &&
2635
      agg_arg_charsets(collation, agg, nagg, MY_COLL_ALLOW_CONV, 1))
2636 2637
    return;
  
2638
  cached_field_type= agg_field_type(agg, nagg);
unknown's avatar
unknown committed
2639 2640 2641 2642
  /*
    Aggregate first expression and all THEN expression types
    and collations when string comparison
  */
2643
  if (first_expr_num != -1)
2644
  {
2645
    uint i;
2646
    agg[0]= args[first_expr_num];
2647 2648
    left_result_type= agg[0]->result_type();

2649
    for (nagg= 0; nagg < ncases/2 ; nagg++)
unknown's avatar
unknown committed
2650
      agg[nagg+1]= args[nagg*2];
2651
    nagg++;
unknown's avatar
unknown committed
2652 2653
    if (!(found_types= collect_cmp_types(agg, nagg)))
      return;
2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668

    for (i= 0; i <= (uint)DECIMAL_RESULT; i++)
    {
      if (found_types & (1 << i) && !cmp_items[i])
      {
        DBUG_ASSERT((Item_result)i != ROW_RESULT);
        if ((Item_result)i == STRING_RESULT &&
            agg_arg_charsets(cmp_collation, agg, nagg, MY_COLL_CMP_CONV, 1))
          return;
        if (!(cmp_items[i]=
            cmp_item::get_comparator((Item_result)i,
                                     cmp_collation.collation)))
          return;
      }
    }
2669
  }
2670

unknown's avatar
unknown committed
2671
  if (else_expr_num == -1 || args[else_expr_num]->maybe_null)
2672
    maybe_null=1;
2673
  
unknown's avatar
unknown committed
2674 2675
  max_length=0;
  decimals=0;
2676
  for (uint i=0 ; i < ncases ; i+=2)
unknown's avatar
unknown committed
2677 2678 2679 2680
  {
    set_if_bigger(max_length,args[i+1]->max_length);
    set_if_bigger(decimals,args[i+1]->decimals);
  }
2681
  if (else_expr_num != -1) 
unknown's avatar
unknown committed
2682
  {
2683 2684
    set_if_bigger(max_length,args[else_expr_num]->max_length);
    set_if_bigger(decimals,args[else_expr_num]->decimals);
unknown's avatar
unknown committed
2685 2686 2687
  }
}

unknown's avatar
unknown committed
2688

unknown's avatar
unknown committed
2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700
uint Item_func_case::decimal_precision() const
{
  int max_int_part=0;
  for (uint i=0 ; i < ncases ; i+=2)
    set_if_bigger(max_int_part, args[i+1]->decimal_int_part());

  if (else_expr_num != -1) 
    set_if_bigger(max_int_part, args[else_expr_num]->decimal_int_part());
  return min(max_int_part + decimals, DECIMAL_MAX_PRECISION);
}


2701
/* TODO:  Fix this so that it prints the whole CASE expression */
unknown's avatar
unknown committed
2702 2703 2704

void Item_func_case::print(String *str)
{
2705
  str->append(STRING_WITH_LEN("(case "));
2706 2707 2708 2709 2710 2711 2712
  if (first_expr_num != -1)
  {
    args[first_expr_num]->print(str);
    str->append(' ');
  }
  for (uint i=0 ; i < ncases ; i+=2)
  {
2713
    str->append(STRING_WITH_LEN("when "));
2714
    args[i]->print(str);
2715
    str->append(STRING_WITH_LEN(" then "));
2716 2717 2718 2719 2720
    args[i+1]->print(str);
    str->append(' ');
  }
  if (else_expr_num != -1)
  {
2721
    str->append(STRING_WITH_LEN("else "));
2722 2723 2724
    args[else_expr_num]->print(str);
    str->append(' ');
  }
2725
  str->append(STRING_WITH_LEN("end)"));
unknown's avatar
unknown committed
2726 2727
}

2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742

void Item_func_case::cleanup()
{
  uint i;
  DBUG_ENTER("Item_func_case::cleanup");
  Item_func::cleanup();
  for (i= 0; i <= (uint)DECIMAL_RESULT; i++)
  {
    delete cmp_items[i];
    cmp_items[i]= 0;
  }
  DBUG_VOID_RETURN;
}


unknown's avatar
unknown committed
2743
/*
2744
  Coalesce - return first not NULL argument.
unknown's avatar
unknown committed
2745 2746
*/

unknown's avatar
unknown committed
2747
String *Item_func_coalesce::str_op(String *str)
unknown's avatar
unknown committed
2748
{
2749
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2750 2751 2752
  null_value=0;
  for (uint i=0 ; i < arg_count ; i++)
  {
unknown's avatar
unknown committed
2753 2754 2755
    String *res;
    if ((res=args[i]->val_str(str)))
      return res;
unknown's avatar
unknown committed
2756 2757 2758 2759 2760
  }
  null_value=1;
  return 0;
}

unknown's avatar
unknown committed
2761
longlong Item_func_coalesce::int_op()
unknown's avatar
unknown committed
2762
{
2763
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774
  null_value=0;
  for (uint i=0 ; i < arg_count ; i++)
  {
    longlong res=args[i]->val_int();
    if (!args[i]->null_value)
      return res;
  }
  null_value=1;
  return 0;
}

unknown's avatar
unknown committed
2775
double Item_func_coalesce::real_op()
unknown's avatar
unknown committed
2776
{
2777
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
2778 2779 2780
  null_value=0;
  for (uint i=0 ; i < arg_count ; i++)
  {
2781
    double res= args[i]->val_real();
unknown's avatar
unknown committed
2782 2783 2784 2785 2786 2787 2788 2789
    if (!args[i]->null_value)
      return res;
  }
  null_value=1;
  return 0;
}


unknown's avatar
unknown committed
2790
my_decimal *Item_func_coalesce::decimal_op(my_decimal *decimal_value)
unknown's avatar
unknown committed
2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804
{
  DBUG_ASSERT(fixed == 1);
  null_value= 0;
  for (uint i= 0; i < arg_count; i++)
  {
    my_decimal *res= args[i]->val_decimal(decimal_value);
    if (!args[i]->null_value)
      return res;
  }
  null_value=1;
  return 0;
}


unknown's avatar
unknown committed
2805 2806
void Item_func_coalesce::fix_length_and_dec()
{
2807
  cached_field_type= agg_field_type(args, arg_count);
unknown's avatar
unknown committed
2808 2809
  agg_result_type(&hybrid_type, args, arg_count);
  switch (hybrid_type) {
unknown's avatar
unknown committed
2810 2811 2812
  case STRING_RESULT:
    count_only_length();
    decimals= NOT_FIXED_DEC;
2813
    agg_arg_charsets(collation, args, arg_count, MY_COLL_ALLOW_CONV, 1);
unknown's avatar
unknown committed
2814 2815 2816 2817 2818 2819 2820 2821 2822
    break;
  case DECIMAL_RESULT:
    count_decimal_length();
    break;
  case REAL_RESULT:
    count_real_length();
    break;
  case INT_RESULT:
    count_only_length();
2823
    decimals= 0;
unknown's avatar
unknown committed
2824 2825
    break;
  case ROW_RESULT:
2826
  default:
unknown's avatar
unknown committed
2827 2828
    DBUG_ASSERT(0);
  }
unknown's avatar
unknown committed
2829 2830 2831
}

/****************************************************************************
2832
 Classes and function for the IN operator
unknown's avatar
unknown committed
2833 2834
****************************************************************************/

unknown's avatar
unknown committed
2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853
/*
  Determine which of the signed longlong arguments is bigger

  SYNOPSIS
    cmp_longs()
      a_val     left argument
      b_val     right argument

  DESCRIPTION
    This function will compare two signed longlong arguments
    and will return -1, 0, or 1 if left argument is smaller than,
    equal to or greater than the right argument.

  RETURN VALUE
    -1          left argument is smaller than the right argument.
    0           left argument is equal to the right argument.
    1           left argument is greater than the right argument.
*/
static inline int cmp_longs (longlong a_val, longlong b_val)
unknown's avatar
unknown committed
2854
{
unknown's avatar
unknown committed
2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915
  return a_val < b_val ? -1 : a_val == b_val ? 0 : 1;
}


/*
  Determine which of the unsigned longlong arguments is bigger

  SYNOPSIS
    cmp_ulongs()
      a_val     left argument
      b_val     right argument

  DESCRIPTION
    This function will compare two unsigned longlong arguments
    and will return -1, 0, or 1 if left argument is smaller than,
    equal to or greater than the right argument.

  RETURN VALUE
    -1          left argument is smaller than the right argument.
    0           left argument is equal to the right argument.
    1           left argument is greater than the right argument.
*/
static inline int cmp_ulongs (ulonglong a_val, ulonglong b_val)
{
  return a_val < b_val ? -1 : a_val == b_val ? 0 : 1;
}


/*
  Compare two integers in IN value list format (packed_longlong) 

  SYNOPSIS
    cmp_longlong()
      cmp_arg   an argument passed to the calling function (qsort2)
      a         left argument
      b         right argument

  DESCRIPTION
    This function will compare two integer arguments in the IN value list
    format and will return -1, 0, or 1 if left argument is smaller than,
    equal to or greater than the right argument.
    It's used in sorting the IN values list and finding an element in it.
    Depending on the signedness of the arguments cmp_longlong() will
    compare them as either signed (using cmp_longs()) or unsigned (using
    cmp_ulongs()).

  RETURN VALUE
    -1          left argument is smaller than the right argument.
    0           left argument is equal to the right argument.
    1           left argument is greater than the right argument.
*/
int cmp_longlong(void *cmp_arg, 
                 in_longlong::packed_longlong *a,
                 in_longlong::packed_longlong *b)
{
  if (a->unsigned_flag != b->unsigned_flag)
  { 
    /* 
      One of the args is unsigned and is too big to fit into the 
      positive signed range. Report no match.
    */  
2916 2917
    if (a->unsigned_flag && ((ulonglong) a->val) > (ulonglong) LONGLONG_MAX ||
        b->unsigned_flag && ((ulonglong) b->val) > (ulonglong) LONGLONG_MAX)
unknown's avatar
unknown committed
2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928
      return a->unsigned_flag ? 1 : -1;
    /*
      Although the signedness differs both args can fit into the signed 
      positive range. Make them signed and compare as usual.
    */  
    return cmp_longs (a->val, b->val);
  }
  if (a->unsigned_flag)
    return cmp_ulongs ((ulonglong) a->val, (ulonglong) b->val);
  else
    return cmp_longs (a->val, b->val);
unknown's avatar
unknown committed
2929 2930
}

2931
static int cmp_double(void *cmp_arg, double *a,double *b)
unknown's avatar
unknown committed
2932 2933 2934 2935
{
  return *a < *b ? -1 : *a == *b ? 0 : 1;
}

unknown's avatar
unknown committed
2936
static int cmp_row(void *cmp_arg, cmp_item_row *a, cmp_item_row *b)
unknown's avatar
unknown committed
2937 2938 2939 2940
{
  return a->compare(b);
}

unknown's avatar
unknown committed
2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953

static int cmp_decimal(void *cmp_arg, my_decimal *a, my_decimal *b)
{
  /*
    We need call of fixing buffer pointer, because fast sort just copy
    decimal buffers in memory and pointers left pointing on old buffer place
  */
  a->fix_buffer_pointer();
  b->fix_buffer_pointer();
  return my_decimal_cmp(a, b);
}


unknown's avatar
unknown committed
2954 2955
int in_vector::find(Item *item)
{
2956
  uchar *result=get_value(item);
unknown's avatar
unknown committed
2957 2958 2959 2960 2961 2962 2963 2964 2965
  if (!result || !used_count)
    return 0;				// Null value

  uint start,end;
  start=0; end=used_count-1;
  while (start != end)
  {
    uint mid=(start+end+1)/2;
    int res;
2966
    if ((res=(*compare)(collation, base+mid*size, result)) == 0)
unknown's avatar
unknown committed
2967 2968 2969 2970 2971 2972
      return 1;
    if (res < 0)
      start=mid;
    else
      end=mid-1;
  }
2973
  return (int) ((*compare)(collation, base+start*size, result) == 0);
unknown's avatar
unknown committed
2974 2975
}

2976 2977
in_string::in_string(uint elements,qsort2_cmp cmp_func, CHARSET_INFO *cs)
  :in_vector(elements, sizeof(String), cmp_func, cs),
2978
   tmp(buff, sizeof(buff), &my_charset_bin)
unknown's avatar
unknown committed
2979 2980 2981 2982
{}

in_string::~in_string()
{
2983
  if (base)
2984
  {
unknown's avatar
unknown committed
2985
    // base was allocated with help of sql_alloc => following is OK
2986 2987
    for (uint i=0 ; i < count ; i++)
      ((String*) base)[i].free();
2988
  }
unknown's avatar
unknown committed
2989 2990 2991 2992 2993 2994 2995
}

void in_string::set(uint pos,Item *item)
{
  String *str=((String*) base)+pos;
  String *res=item->val_str(str);
  if (res && res != str)
2996 2997 2998
  {
    if (res->uses_buffer_owned_by(str))
      res->copy();
unknown's avatar
unknown committed
2999
    *str= *res;
3000
  }
3001
  if (!str->charset())
3002 3003
  {
    CHARSET_INFO *cs;
3004
    if (!(cs= item->collation.collation))
3005
      cs= &my_charset_bin;		// Should never happen for STR items
3006 3007
    str->set_charset(cs);
  }
unknown's avatar
unknown committed
3008 3009
}

3010

3011
uchar *in_string::get_value(Item *item)
unknown's avatar
unknown committed
3012
{
3013
  return (uchar*) item->val_str(&tmp);
unknown's avatar
unknown committed
3014 3015
}

unknown's avatar
unknown committed
3016 3017
in_row::in_row(uint elements, Item * item)
{
3018
  base= (char*) new cmp_item_row[count= elements];
unknown's avatar
unknown committed
3019
  size= sizeof(cmp_item_row);
3020
  compare= (qsort2_cmp) cmp_row;
3021 3022 3023 3024 3025 3026
  /*
    We need to reset these as otherwise we will call sort() with
    uninitialized (even if not used) elements
  */
  used_count= elements;
  collation= 0;
3027 3028 3029 3030 3031
}

in_row::~in_row()
{
  if (base)
3032
    delete [] (cmp_item_row*) base;
unknown's avatar
unknown committed
3033 3034
}

3035
uchar *in_row::get_value(Item *item)
unknown's avatar
unknown committed
3036 3037
{
  tmp.store_value(item);
unknown's avatar
unknown committed
3038 3039
  if (item->is_null())
    return 0;
3040
  return (uchar *)&tmp;
unknown's avatar
unknown committed
3041 3042 3043 3044 3045
}

void in_row::set(uint pos, Item *item)
{
  DBUG_ENTER("in_row::set");
unknown's avatar
unknown committed
3046
  DBUG_PRINT("enter", ("pos: %u  item: 0x%lx", pos, (ulong) item));
unknown's avatar
unknown committed
3047 3048 3049
  ((cmp_item_row*) base)[pos].store_value_by_template(&tmp, item);
  DBUG_VOID_RETURN;
}
unknown's avatar
unknown committed
3050 3051

in_longlong::in_longlong(uint elements)
unknown's avatar
unknown committed
3052
  :in_vector(elements,sizeof(packed_longlong),(qsort2_cmp) cmp_longlong, 0)
unknown's avatar
unknown committed
3053 3054 3055 3056
{}

void in_longlong::set(uint pos,Item *item)
{
unknown's avatar
unknown committed
3057 3058 3059 3060
  struct packed_longlong *buff= &((packed_longlong*) base)[pos];
  
  buff->val= item->val_int();
  buff->unsigned_flag= item->unsigned_flag;
unknown's avatar
unknown committed
3061 3062
}

3063
uchar *in_longlong::get_value(Item *item)
unknown's avatar
unknown committed
3064
{
unknown's avatar
unknown committed
3065
  tmp.val= item->val_int();
unknown's avatar
unknown committed
3066
  if (item->null_value)
unknown's avatar
unknown committed
3067
    return 0;
unknown's avatar
unknown committed
3068
  tmp.unsigned_flag= item->unsigned_flag;
3069
  return (uchar*) &tmp;
unknown's avatar
unknown committed
3070 3071
}

3072 3073
void in_datetime::set(uint pos,Item *item)
{
3074
  Item **tmp_item= &item;
3075 3076 3077
  bool is_null;
  struct packed_longlong *buff= &((packed_longlong*) base)[pos];

3078
  buff->val= get_datetime_value(thd, &tmp_item, 0, warn_item, &is_null);
3079 3080 3081
  buff->unsigned_flag= 1L;
}

unknown's avatar
unknown committed
3082
uchar *in_datetime::get_value(Item *item)
3083 3084 3085 3086 3087 3088 3089
{
  bool is_null;
  Item **tmp_item= lval_cache ? &lval_cache : &item;
  tmp.val= get_datetime_value(thd, &tmp_item, &lval_cache, warn_item, &is_null);
  if (item->null_value)
    return 0;
  tmp.unsigned_flag= 1L;
unknown's avatar
unknown committed
3090
  return (uchar*) &tmp;
3091 3092
}

unknown's avatar
unknown committed
3093
in_double::in_double(uint elements)
3094
  :in_vector(elements,sizeof(double),(qsort2_cmp) cmp_double, 0)
unknown's avatar
unknown committed
3095 3096 3097 3098
{}

void in_double::set(uint pos,Item *item)
{
3099
  ((double*) base)[pos]= item->val_real();
unknown's avatar
unknown committed
3100 3101
}

3102
uchar *in_double::get_value(Item *item)
unknown's avatar
unknown committed
3103
{
3104
  tmp= item->val_real();
unknown's avatar
unknown committed
3105
  if (item->null_value)
3106
    return 0;					/* purecov: inspected */
3107
  return (uchar*) &tmp;
unknown's avatar
unknown committed
3108 3109
}

unknown's avatar
unknown committed
3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122

in_decimal::in_decimal(uint elements)
  :in_vector(elements, sizeof(my_decimal),(qsort2_cmp) cmp_decimal, 0)
{}


void in_decimal::set(uint pos, Item *item)
{
  /* as far as 'item' is constant, we can store reference on my_decimal */
  my_decimal *dec= ((my_decimal *)base) + pos;
  dec->len= DECIMAL_BUFF_LENGTH;
  dec->fix_buffer_pointer();
  my_decimal *res= item->val_decimal(dec);
3123 3124
  /* if item->val_decimal() is evaluated to NULL then res == 0 */ 
  if (!item->null_value && res != dec)
unknown's avatar
unknown committed
3125 3126 3127 3128
    my_decimal2decimal(res, dec);
}


3129
uchar *in_decimal::get_value(Item *item)
unknown's avatar
unknown committed
3130 3131 3132 3133
{
  my_decimal *result= item->val_decimal(&val);
  if (item->null_value)
    return 0;
3134
  return (uchar *)result;
unknown's avatar
unknown committed
3135 3136 3137 3138 3139
}


cmp_item* cmp_item::get_comparator(Item_result type,
                                   CHARSET_INFO *cs)
3140
{
unknown's avatar
unknown committed
3141
  switch (type) {
3142
  case STRING_RESULT:
unknown's avatar
unknown committed
3143
    return new cmp_item_sort_string(cs);
3144 3145 3146 3147 3148 3149
  case INT_RESULT:
    return new cmp_item_int;
  case REAL_RESULT:
    return new cmp_item_real;
  case ROW_RESULT:
    return new cmp_item_row;
unknown's avatar
unknown committed
3150 3151
  case DECIMAL_RESULT:
    return new cmp_item_decimal;
unknown's avatar
unknown committed
3152 3153 3154
  default:
    DBUG_ASSERT(0);
    break;
3155 3156 3157 3158
  }
  return 0; // to satisfy compiler :)
}

3159

unknown's avatar
unknown committed
3160 3161
cmp_item* cmp_item_sort_string::make_same()
{
3162
  return new cmp_item_sort_string_in_static(cmp_charset);
unknown's avatar
unknown committed
3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179
}

cmp_item* cmp_item_int::make_same()
{
  return new cmp_item_int();
}

cmp_item* cmp_item_real::make_same()
{
  return new cmp_item_real();
}

cmp_item* cmp_item_row::make_same()
{
  return new cmp_item_row();
}

3180 3181 3182 3183

cmp_item_row::~cmp_item_row()
{
  DBUG_ENTER("~cmp_item_row");
unknown's avatar
unknown committed
3184
  DBUG_PRINT("enter",("this: 0x%lx", (long) this));
3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196
  if (comparators)
  {
    for (uint i= 0; i < n; i++)
    {
      if (comparators[i])
	delete comparators[i];
    }
  }
  DBUG_VOID_RETURN;
}


3197 3198 3199 3200 3201 3202 3203
void cmp_item_row::alloc_comparators()
{
  if (!comparators)
    comparators= (cmp_item **) current_thd->calloc(sizeof(cmp_item *)*n);
}


3204 3205
void cmp_item_row::store_value(Item *item)
{
3206
  DBUG_ENTER("cmp_item_row::store_value");
3207
  n= item->cols();
3208
  alloc_comparators();
3209
  if (comparators)
3210
  {
3211
    item->bring_value();
unknown's avatar
unknown committed
3212
    item->null_value= 0;
3213
    for (uint i=0; i < n; i++)
3214
    {
unknown's avatar
unknown committed
3215
      if (!comparators[i])
unknown's avatar
unknown committed
3216
        if (!(comparators[i]=
3217 3218
              cmp_item::get_comparator(item->element_index(i)->result_type(),
                                       item->element_index(i)->collation.collation)))
unknown's avatar
unknown committed
3219
	  break;					// new failed
3220 3221
      comparators[i]->store_value(item->element_index(i));
      item->null_value|= item->element_index(i)->null_value;
3222
    }
3223
  }
3224
  DBUG_VOID_RETURN;
3225 3226
}

3227

unknown's avatar
unknown committed
3228 3229 3230 3231 3232
void cmp_item_row::store_value_by_template(cmp_item *t, Item *item)
{
  cmp_item_row *tmpl= (cmp_item_row*) t;
  if (tmpl->n != item->cols())
  {
unknown's avatar
unknown committed
3233
    my_error(ER_OPERAND_COLUMNS, MYF(0), tmpl->n);
unknown's avatar
unknown committed
3234 3235 3236 3237 3238
    return;
  }
  n= tmpl->n;
  if ((comparators= (cmp_item **) sql_alloc(sizeof(cmp_item *)*n)))
  {
3239
    item->bring_value();
unknown's avatar
unknown committed
3240 3241
    item->null_value= 0;
    for (uint i=0; i < n; i++)
3242 3243 3244 3245
    {
      if (!(comparators[i]= tmpl->comparators[i]->make_same()))
	break;					// new failed
      comparators[i]->store_value_by_template(tmpl->comparators[i],
3246 3247
					      item->element_index(i));
      item->null_value|= item->element_index(i)->null_value;
3248
    }
unknown's avatar
unknown committed
3249 3250 3251
  }
}

3252

3253 3254
int cmp_item_row::cmp(Item *arg)
{
unknown's avatar
unknown committed
3255 3256 3257
  arg->null_value= 0;
  if (arg->cols() != n)
  {
unknown's avatar
unknown committed
3258
    my_error(ER_OPERAND_COLUMNS, MYF(0), n);
unknown's avatar
unknown committed
3259 3260
    return 1;
  }
unknown's avatar
unknown committed
3261
  bool was_null= 0;
3262
  arg->bring_value();
unknown's avatar
unknown committed
3263
  for (uint i=0; i < n; i++)
3264
  {
3265
    if (comparators[i]->cmp(arg->element_index(i)))
unknown's avatar
unknown committed
3266
    {
3267
      if (!arg->element_index(i)->null_value)
unknown's avatar
unknown committed
3268 3269
	return 1;
      was_null= 1;
unknown's avatar
unknown committed
3270
    }
3271
  }
unknown's avatar
unknown committed
3272
  return (arg->null_value= was_null);
unknown's avatar
unknown committed
3273 3274
}

3275

unknown's avatar
unknown committed
3276 3277
int cmp_item_row::compare(cmp_item *c)
{
3278
  cmp_item_row *l_cmp= (cmp_item_row *) c;
unknown's avatar
unknown committed
3279
  for (uint i=0; i < n; i++)
3280 3281
  {
    int res;
3282
    if ((res= comparators[i]->compare(l_cmp->comparators[i])))
unknown's avatar
unknown committed
3283
      return res;
3284
  }
3285 3286
  return 0;
}
unknown's avatar
unknown committed
3287

3288

unknown's avatar
unknown committed
3289 3290 3291
void cmp_item_decimal::store_value(Item *item)
{
  my_decimal *val= item->val_decimal(&value);
unknown's avatar
unknown committed
3292 3293
  /* val may be zero if item is nnull */
  if (val && val != &value)
unknown's avatar
unknown committed
3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306
    my_decimal2decimal(val, &value);
}


int cmp_item_decimal::cmp(Item *arg)
{
  my_decimal tmp_buf, *tmp= arg->val_decimal(&tmp_buf);
  if (arg->null_value)
    return 1;
  return my_decimal_cmp(&value, tmp);
}


unknown's avatar
unknown committed
3307
int cmp_item_decimal::compare(cmp_item *arg)
unknown's avatar
unknown committed
3308
{
3309 3310
  cmp_item_decimal *l_cmp= (cmp_item_decimal*) arg;
  return my_decimal_cmp(&value, &l_cmp->value);
unknown's avatar
unknown committed
3311 3312 3313 3314 3315 3316 3317 3318 3319
}


cmp_item* cmp_item_decimal::make_same()
{
  return new cmp_item_decimal();
}


3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349
void cmp_item_datetime::store_value(Item *item)
{
  bool is_null;
  Item **tmp_item= lval_cache ? &lval_cache : &item;
  value= get_datetime_value(thd, &tmp_item, &lval_cache, warn_item, &is_null);
}


int cmp_item_datetime::cmp(Item *arg)
{
  bool is_null;
  Item **tmp_item= &arg;
  return value !=
    get_datetime_value(thd, &tmp_item, 0, warn_item, &is_null);
}


int cmp_item_datetime::compare(cmp_item *ci)
{
  cmp_item_datetime *l_cmp= (cmp_item_datetime *)ci;
  return (value < l_cmp->value) ? -1 : ((value == l_cmp->value) ? 0 : 1);
}


cmp_item *cmp_item_datetime::make_same()
{
  return new cmp_item_datetime(warn_item);
}


unknown's avatar
unknown committed
3350 3351 3352
bool Item_func_in::nulls_in_row()
{
  Item **arg,**arg_end;
3353
  for (arg= args+1, arg_end= args+arg_count; arg != arg_end ; arg++)
unknown's avatar
unknown committed
3354 3355 3356 3357 3358 3359 3360
  {
    if ((*arg)->null_inside())
      return 1;
  }
  return 0;
}

3361

unknown's avatar
unknown committed
3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391
/*
  Perform context analysis of an IN item tree

  SYNOPSIS:
    fix_fields()
    thd     reference to the global context of the query thread
    tables  list of all open tables involved in the query
    ref     pointer to Item* variable where pointer to resulting "fixed"
            item is to be assigned

  DESCRIPTION
    This function performs context analysis (name resolution) and calculates
    various attributes of the item tree with Item_func_in as its root.
    The function saves in ref the pointer to the item or to a newly created
    item that is considered as a replacement for the original one.

  NOTES
    Let T0(e)/T1(e) be the value of not_null_tables(e) when e is used on
    a predicate/function level. Then it's easy to show that:
      T0(e IN(e1,...,en))     = union(T1(e),intersection(T1(ei)))
      T1(e IN(e1,...,en))     = union(T1(e),intersection(T1(ei)))
      T0(e NOT IN(e1,...,en)) = union(T1(e),union(T1(ei)))
      T1(e NOT IN(e1,...,en)) = union(T1(e),intersection(T1(ei)))

  RETURN
    0   ok
    1   got error
*/

bool
3392
Item_func_in::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
3393 3394 3395
{
  Item **arg, **arg_end;

3396
  if (Item_func_opt_neg::fix_fields(thd, ref))
unknown's avatar
unknown committed
3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411
    return 1;

  /* not_null_tables_cache == union(T1(e),union(T1(ei))) */
  if (pred_level && negated)
    return 0;

  /* not_null_tables_cache = union(T1(e),intersection(T1(ei))) */
  not_null_tables_cache= ~(table_map) 0;
  for (arg= args + 1, arg_end= args + arg_count; arg != arg_end; arg++)
    not_null_tables_cache&= (*arg)->not_null_tables();
  not_null_tables_cache|= (*args)->not_null_tables();
  return 0;
}


3412
static int srtcmp_in(CHARSET_INFO *cs, const String *x,const String *y)
3413
{
3414
  return cs->coll->strnncollsp(cs,
unknown's avatar
unknown committed
3415
                               (uchar *) x->ptr(),x->length(),
3416
                               (uchar *) y->ptr(),y->length(), 0);
3417 3418
}

3419

unknown's avatar
unknown committed
3420 3421
void Item_func_in::fix_length_and_dec()
{
3422
  Item **arg, **arg_end;
3423
  bool const_itm= 1;
3424
  THD *thd= current_thd;
3425 3426 3427 3428
  bool datetime_found= FALSE;
  /* TRUE <=> arguments values will be compared as DATETIMEs. */
  bool compare_as_datetime= FALSE;
  Item *date_arg= 0;
3429 3430 3431 3432 3433 3434 3435
  uint found_types= 0;
  uint type_cnt= 0, i;
  Item_result cmp_type= STRING_RESULT;
  left_result_type= args[0]->result_type();
  if (!(found_types= collect_cmp_types(args, arg_count)))
    return;
  
3436
  for (arg= args + 1, arg_end= args + arg_count; arg != arg_end ; arg++)
unknown's avatar
unknown committed
3437 3438 3439 3440 3441 3442 3443
  {
    if (!arg[0]->const_item())
    {
      const_itm= 0;
      break;
    }
  }
3444 3445 3446
  for (i= 0; i <= (uint)DECIMAL_RESULT; i++)
  {
    if (found_types & 1 << i)
3447
    {
3448
      (type_cnt)++;
3449 3450
      cmp_type= (Item_result) i;
    }
3451
  }
3452 3453 3454 3455 3456 3457 3458 3459

  if (type_cnt == 1)
  {
    if (cmp_type == STRING_RESULT && 
        agg_arg_charsets(cmp_collation, args, arg_count, MY_COLL_CMP_CONV, 1))
      return;
    arg_types_compatible= TRUE;
  }
3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486
  if (type_cnt == 1)
  {
    /*
      When comparing rows create the row comparator object beforehand to ease
      the DATETIME comparison detection procedure.
    */
    if (cmp_type == ROW_RESULT)
    {
      cmp_item_row *cmp= 0;
      if (const_itm && !nulls_in_row())
      {
        array= new in_row(arg_count-1, 0);
        cmp= &((in_row*)array)->tmp;
      }
      else
      {
        if (!(cmp= new cmp_item_row))
          return;
        cmp_items[ROW_RESULT]= cmp;
      }
      cmp->n= args[0]->cols();
      cmp->alloc_comparators();
    }
    /* All DATE/DATETIME fields/functions has the STRING result type. */
    if (cmp_type == STRING_RESULT || cmp_type == ROW_RESULT)
    {
      uint col, cols= args[0]->cols();
3487

3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543
      for (col= 0; col < cols; col++)
      {
        bool skip_column= FALSE;
        /*
          Check that all items to be compared has the STRING result type and at
          least one of them is a DATE/DATETIME item.
        */
        for (arg= args, arg_end= args + arg_count; arg != arg_end ; arg++)
        {
          Item *itm= ((cmp_type == STRING_RESULT) ? arg[0] :
                      arg[0]->element_index(col));
          if (itm->result_type() != STRING_RESULT)
          {
            skip_column= TRUE;
            break;
          }
          else if (itm->is_datetime())
          {
            datetime_found= TRUE;
            /*
              Internally all DATE/DATETIME values are converted to the DATETIME
              type. So try to find a DATETIME item to issue correct warnings.
            */
            if (!date_arg)
              date_arg= itm;
            else if (itm->field_type() == MYSQL_TYPE_DATETIME)
            {
              date_arg= itm;
              /* All arguments are already checked to have the STRING result. */
              if (cmp_type == STRING_RESULT)
                break;
            }
          }
        }
        if (skip_column)
          continue;
        if (datetime_found)
        {
          if (cmp_type == ROW_RESULT)
          {
            cmp_item **cmp= 0;
            if (array)
              cmp= ((in_row*)array)->tmp.comparators + col;
            else
              cmp= ((cmp_item_row*)cmp_items[ROW_RESULT])->comparators + col;
            *cmp= new cmp_item_datetime(date_arg);
            /* Reset variables for the next column. */
            date_arg= 0;
            datetime_found= FALSE;
          }
          else
            compare_as_datetime= TRUE;
        }
      }
    }
  }
unknown's avatar
unknown committed
3544
  /*
3545
    Row item with NULLs inside can return NULL or FALSE =>
unknown's avatar
unknown committed
3546 3547
    they can't be processed as static
  */
3548
  if (type_cnt == 1 && const_itm && !nulls_in_row())
unknown's avatar
unknown committed
3549
  {
3550 3551 3552
    if (compare_as_datetime)
      array= new in_datetime(date_arg, arg_count - 1);
    else
unknown's avatar
unknown committed
3553
    {
3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564
      /*
        IN must compare INT columns and constants as int values (the same
        way as equality does).
        So we must check here if the column on the left and all the constant 
        values on the right can be compared as integers and adjust the 
        comparison type accordingly.
      */  
      if (args[0]->real_item()->type() == FIELD_ITEM &&
          thd->lex->sql_command != SQLCOM_CREATE_VIEW &&
          thd->lex->sql_command != SQLCOM_SHOW_CREATE &&
          cmp_type != INT_RESULT)
unknown's avatar
unknown committed
3565
      {
3566 3567
        Field *field= ((Item_field*) (args[0]->real_item()))->field;
        if (field->can_be_compared_as_longlong())
unknown's avatar
unknown committed
3568
        {
3569 3570 3571 3572 3573 3574 3575 3576
          bool all_converted= TRUE;
          for (arg=args+1, arg_end=args+arg_count; arg != arg_end ; arg++)
          {
            if (!convert_constant_item (thd, field, &arg[0]))
              all_converted= FALSE;
          }
          if (all_converted)
            cmp_type= INT_RESULT;
unknown's avatar
unknown committed
3577 3578
        }
      }
3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604
      switch (cmp_type) {
      case STRING_RESULT:
        array=new in_string(arg_count-1,(qsort2_cmp) srtcmp_in, 
                            cmp_collation.collation);
        break;
      case INT_RESULT:
        array= new in_longlong(arg_count-1);
        break;
      case REAL_RESULT:
        array= new in_double(arg_count-1);
        break;
      case ROW_RESULT:
        /*
          The row comparator was created at the beginning but only DATETIME
          items comparators were initialized. Call store_value() to setup
          others.
        */
        ((in_row*)array)->tmp.store_value(args[0]);
        break;
      case DECIMAL_RESULT:
        array= new in_decimal(arg_count - 1);
        break;
      default:
        DBUG_ASSERT(0);
        return;
      }
unknown's avatar
unknown committed
3605
    }
3606
    if (array && !(thd->is_fatal_error))		// If not EOM
unknown's avatar
unknown committed
3607
    {
unknown's avatar
unknown committed
3608
      uint j=0;
unknown's avatar
unknown committed
3609
      for (uint i=1 ; i < arg_count ; i++)
unknown's avatar
unknown committed
3610 3611 3612 3613
      {
	array->set(j,args[i]);
	if (!args[i]->null_value)			// Skip NULL values
	  j++;
unknown's avatar
unknown committed
3614 3615
	else
	  have_null= 1;
unknown's avatar
unknown committed
3616
      }
3617
      if ((array->used_count= j))
unknown's avatar
unknown committed
3618
	array->sort();
unknown's avatar
unknown committed
3619 3620 3621 3622
    }
  }
  else
  {
3623 3624
    if (compare_as_datetime)
      cmp_items[STRING_RESULT]= new cmp_item_datetime(date_arg);
3625
    else
3626
    {
3627
      for (i= 0; i <= (uint) DECIMAL_RESULT; i++)
3628
      {
3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639
        if (found_types & (1 << i) && !cmp_items[i])
        {
          if ((Item_result)i == STRING_RESULT &&
              agg_arg_charsets(cmp_collation, args, arg_count,
                               MY_COLL_CMP_CONV, 1))
            return;
          if (!cmp_items[i] && !(cmp_items[i]=
              cmp_item::get_comparator((Item_result)i,
                                       cmp_collation.collation)))
            return;
        }
3640 3641
      }
    }
unknown's avatar
unknown committed
3642
  }
unknown's avatar
unknown committed
3643
  max_length= 1;
unknown's avatar
unknown committed
3644 3645 3646 3647 3648 3649
}


void Item_func_in::print(String *str)
{
  str->append('(');
3650
  args[0]->print(str);
unknown's avatar
unknown committed
3651
  if (negated)
3652 3653
    str->append(STRING_WITH_LEN(" not"));
  str->append(STRING_WITH_LEN(" in ("));
unknown's avatar
unknown committed
3654
  print_args(str, 1);
3655
  str->append(STRING_WITH_LEN("))"));
unknown's avatar
unknown committed
3656 3657 3658
}


3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683
/*
  Evaluate the function and return its value.

  SYNOPSIS
    val_int()

  DESCRIPTION
    Evaluate the function and return its value.

  IMPLEMENTATION
    If the array object is defined then the value of the function is
    calculated by means of this array.
    Otherwise several cmp_item objects are used in order to do correct
    comparison of left expression and an expression from the values list.
    One cmp_item object correspond to one used comparison type. Left
    expression can be evaluated up to number of different used comparison
    types. A bit mapped variable value_added_map is used to check whether
    the left expression already was evaluated for a particular result type.
    Result types are mapped to it according to their integer values i.e.
    STRING_RESULT is mapped to bit 0, REAL_RESULT to bit 1, so on.

  RETURN
    Value of the function
*/

unknown's avatar
unknown committed
3684 3685
longlong Item_func_in::val_int()
{
3686
  cmp_item *in_item;
3687
  DBUG_ASSERT(fixed == 1);
3688
  uint value_added_map= 0;
unknown's avatar
unknown committed
3689 3690
  if (array)
  {
3691 3692
    int tmp=array->find(args[0]);
    null_value=args[0]->null_value || (!tmp && have_null);
unknown's avatar
unknown committed
3693
    return (longlong) (!null_value && tmp != negated);
unknown's avatar
unknown committed
3694
  }
3695 3696

  for (uint i= 1 ; i < arg_count ; i++)
unknown's avatar
unknown committed
3697
  {
3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708
    Item_result cmp_type= item_cmp_type(left_result_type, args[i]->result_type());
    in_item= cmp_items[(uint)cmp_type];
    DBUG_ASSERT(in_item);
    if (!(value_added_map & (1 << (uint)cmp_type)))
    {
      in_item->store_value(args[0]);
      if ((null_value=args[0]->null_value))
        return 0;
      have_null= 0;
      value_added_map|= 1 << (uint)cmp_type;
    }
unknown's avatar
unknown committed
3709
    if (!in_item->cmp(args[i]) && !args[i]->null_value)
unknown's avatar
unknown committed
3710
      return (longlong) (!negated);
3711
    have_null|= args[i]->null_value;
unknown's avatar
unknown committed
3712
  }
3713

3714
  null_value= have_null;
unknown's avatar
unknown committed
3715
  return (longlong) (!null_value && negated);
unknown's avatar
unknown committed
3716 3717 3718 3719 3720
}


longlong Item_func_bit_or::val_int()
{
3721
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740
  ulonglong arg1= (ulonglong) args[0]->val_int();
  if (args[0]->null_value)
  {
    null_value=1; /* purecov: inspected */
    return 0; /* purecov: inspected */
  }
  ulonglong arg2= (ulonglong) args[1]->val_int();
  if (args[1]->null_value)
  {
    null_value=1;
    return 0;
  }
  null_value=0;
  return (longlong) (arg1 | arg2);
}


longlong Item_func_bit_and::val_int()
{
3741
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757
  ulonglong arg1= (ulonglong) args[0]->val_int();
  if (args[0]->null_value)
  {
    null_value=1; /* purecov: inspected */
    return 0; /* purecov: inspected */
  }
  ulonglong arg2= (ulonglong) args[1]->val_int();
  if (args[1]->null_value)
  {
    null_value=1; /* purecov: inspected */
    return 0; /* purecov: inspected */
  }
  null_value=0;
  return (longlong) (arg1 & arg2);
}

3758
Item_cond::Item_cond(THD *thd, Item_cond *item)
3759
  :Item_bool_func(thd, item),
3760 3761
   abort_on_null(item->abort_on_null),
   and_tables_cache(item->and_tables_cache)
3762 3763
{
  /*
unknown's avatar
unknown committed
3764
    item->list will be copied by copy_andor_arguments() call
3765 3766 3767
  */
}

unknown's avatar
unknown committed
3768

3769 3770 3771
void Item_cond::copy_andor_arguments(THD *thd, Item_cond *item)
{
  List_iterator_fast<Item> li(item->list);
unknown's avatar
unknown committed
3772
  while (Item *it= li++)
3773 3774
    list.push_back(it->copy_andor_structure(thd));
}
unknown's avatar
unknown committed
3775

unknown's avatar
unknown committed
3776

unknown's avatar
unknown committed
3777
bool
3778
Item_cond::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
3779
{
3780
  DBUG_ASSERT(fixed == 0);
unknown's avatar
unknown committed
3781 3782
  List_iterator<Item> li(list);
  Item *item;
3783
#ifndef EMBEDDED_LIBRARY
3784
  uchar buff[sizeof(char*)];			// Max local vars in function
3785
#endif
3786
  not_null_tables_cache= used_tables_cache= 0;
unknown's avatar
unknown committed
3787
  const_item_cache= 1;
3788 3789 3790 3791 3792
  /*
    and_table_cache is the value that Item_cond_or() returns for
    not_null_tables()
  */
  and_tables_cache= ~(table_map) 0;
unknown's avatar
unknown committed
3793

3794
  if (check_stack_overrun(thd, STACK_MIN_SIZE, buff))
unknown's avatar
unknown committed
3795
    return TRUE;				// Fatal error flag is set!
3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810
  /*
    The following optimization reduces the depth of an AND-OR tree.
    E.g. a WHERE clause like
      F1 AND (F2 AND (F2 AND F4))
    is parsed into a tree with the same nested structure as defined
    by braces. This optimization will transform such tree into
      AND (F1, F2, F3, F4).
    Trees of OR items are flattened as well:
      ((F1 OR F2) OR (F3 OR F4))   =>   OR (F1, F2, F3, F4)
    Items for removed AND/OR levels will dangle until the death of the
    entire statement.
    The optimization is currently prepared statements and stored procedures
    friendly as it doesn't allocate any memory and its effects are durable
    (i.e. do not depend on PS/SP arguments).
  */
unknown's avatar
unknown committed
3811 3812
  while ((item=li++))
  {
3813
    table_map tmp_table_map;
unknown's avatar
unknown committed
3814
    while (item->type() == Item::COND_ITEM &&
3815 3816
	   ((Item_cond*) item)->functype() == functype() &&
           !((Item_cond*) item)->list.is_empty())
unknown's avatar
unknown committed
3817 3818 3819 3820 3821
    {						// Identical function
      li.replace(((Item_cond*) item)->list);
      ((Item_cond*) item)->list.empty();
      item= *li.ref();				// new current item
    }
3822 3823
    if (abort_on_null)
      item->top_level_item();
3824 3825

    // item can be substituted in fix_fields
3826
    if ((!item->fixed &&
3827
	 item->fix_fields(thd, li.ref())) ||
3828
	(item= *li.ref())->check_cols(1))
unknown's avatar
unknown committed
3829
      return TRUE; /* purecov: inspected */
3830
    used_tables_cache|=     item->used_tables();
unknown's avatar
unknown committed
3831 3832 3833
    if (item->const_item())
      and_tables_cache= (table_map) 0;
    else
unknown's avatar
unknown committed
3834 3835 3836 3837 3838 3839
    {
      tmp_table_map= item->not_null_tables();
      not_null_tables_cache|= tmp_table_map;
      and_tables_cache&= tmp_table_map;
      const_item_cache= FALSE;
    }  
3840
    with_sum_func=	    with_sum_func || item->with_sum_func;
3841
    with_subselect|=        item->with_subselect;
unknown's avatar
unknown committed
3842 3843
    if (item->maybe_null)
      maybe_null=1;
unknown's avatar
unknown committed
3844
  }
3845
  thd->lex->current_select->cond_count+= list.elements;
unknown's avatar
unknown committed
3846
  fix_length_and_dec();
3847
  fixed= 1;
unknown's avatar
unknown committed
3848
  return FALSE;
unknown's avatar
unknown committed
3849 3850
}

3851
bool Item_cond::walk(Item_processor processor, bool walk_subquery, uchar *arg)
unknown's avatar
unknown committed
3852 3853 3854 3855
{
  List_iterator_fast<Item> li(list);
  Item *item;
  while ((item= li++))
3856
    if (item->walk(processor, walk_subquery, arg))
unknown's avatar
unknown committed
3857
      return 1;
3858
  return Item_func::walk(processor, walk_subquery, arg);
unknown's avatar
unknown committed
3859 3860
}

unknown's avatar
unknown committed
3861 3862 3863 3864 3865 3866

/*
  Transform an Item_cond object with a transformer callback function
   
  SYNOPSIS
    transform()
3867 3868 3869
      transformer   the transformer callback function to be applied to the nodes
                    of the tree of the object
      arg           parameter to be passed to the transformer
unknown's avatar
unknown committed
3870 3871
  
  DESCRIPTION
3872 3873
    The function recursively applies the transform method to each
     member item of the condition list.
unknown's avatar
unknown committed
3874 3875
    If the call of the method for a member item returns a new item
    the old item is substituted for a new one.
3876
    After this the transformer is applied to the root node
unknown's avatar
unknown committed
3877 3878 3879 3880 3881 3882
    of the Item_cond object. 
     
  RETURN VALUES
    Item returned as the result of transformation of the root node 
*/

3883
Item *Item_cond::transform(Item_transformer transformer, uchar *arg)
3884
{
3885 3886
  DBUG_ASSERT(!current_thd->is_stmt_prepare());

3887 3888 3889 3890
  List_iterator<Item> li(list);
  Item *item;
  while ((item= li++))
  {
unknown's avatar
unknown committed
3891
    Item *new_item= item->transform(transformer, arg);
3892 3893
    if (!new_item)
      return 0;
3894 3895 3896 3897 3898 3899 3900

    /*
      THD::change_item_tree() should be called only if the tree was
      really transformed, i.e. when a new item has been created.
      Otherwise we'll be allocating a lot of unnecessary memory for
      change records at each execution.
    */
3901
    if (new_item != item)
3902
      current_thd->change_item_tree(li.ref(), new_item);
3903
  }
unknown's avatar
unknown committed
3904
  return Item_func::transform(transformer, arg);
3905 3906
}

3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933

/*
  Compile Item_cond object with a processor and a transformer callback functions
   
  SYNOPSIS
    compile()
      analyzer      the analyzer callback function to be applied to the nodes
                    of the tree of the object
      arg_p         in/out parameter to be passed to the analyzer
      transformer   the transformer callback function to be applied to the nodes
                    of the tree of the object
      arg_t         parameter to be passed to the transformer
  
  DESCRIPTION
    First the function applies the analyzer to the root node of
    the Item_func object. Then if the analyzer succeeeds (returns TRUE)
    the function recursively applies the compile method to member
    item of the condition list.
    If the call of the method for a member item returns a new item
    the old item is substituted for a new one.
    After this the transformer is applied to the root node
    of the Item_cond object. 
     
  RETURN VALUES
    Item returned as the result of transformation of the root node 
*/

3934 3935
Item *Item_cond::compile(Item_analyzer analyzer, uchar **arg_p,
                         Item_transformer transformer, uchar *arg_t)
3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947
{
  if (!(this->*analyzer)(arg_p))
    return 0;
  
  List_iterator<Item> li(list);
  Item *item;
  while ((item= li++))
  {
    /* 
      The same parameter value of arg_p must be passed
      to analyze any argument of the condition formula.
    */   
3948
    uchar *arg_v= *arg_p;
3949 3950 3951 3952 3953 3954 3955
    Item *new_item= item->compile(analyzer, &arg_v, transformer, arg_t);
    if (new_item && new_item != item)
      li.replace(new_item);
  }
  return Item_func::transform(transformer, arg_t);
}

3956 3957
void Item_cond::traverse_cond(Cond_traverser traverser,
                              void *arg, traverse_order order)
3958 3959 3960 3961
{
  List_iterator<Item> li(list);
  Item *item;

3962 3963 3964 3965 3966 3967 3968
  switch(order) {
  case(PREFIX):
    (*traverser)(this, arg);
    while ((item= li++))
    {
      item->traverse_cond(traverser, arg, order);
    }
3969
    (*traverser)(NULL, arg);
3970 3971 3972 3973 3974 3975 3976
    break;
  case(POSTFIX):
    while ((item= li++))
    {
      item->traverse_cond(traverser, arg, order);
    }
    (*traverser)(this, arg);
3977 3978
  }
}
unknown's avatar
unknown committed
3979

3980 3981 3982 3983
/*
  Move SUM items out from item tree and replace with reference

  SYNOPSIS
3984 3985 3986 3987
    split_sum_func()
    thd			Thread handler
    ref_pointer_array	Pointer to array of reference fields
    fields		All fields in select
3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998

  NOTES
   This function is run on all expression (SELECT list, WHERE, HAVING etc)
   that have or refer (HAVING) to a SUM expression.

   The split is done to get an unique item for each SUM function
   so that we can easily find and calculate them.
   (Calculation done by update_sum_func() and copy_sum_funcs() in
   sql_select.cc)
*/

3999 4000
void Item_cond::split_sum_func(THD *thd, Item **ref_pointer_array,
                               List<Item> &fields)
unknown's avatar
unknown committed
4001 4002 4003
{
  List_iterator<Item> li(list);
  Item *item;
4004
  while ((item= li++))
unknown's avatar
unknown committed
4005
    item->split_sum_func2(thd, ref_pointer_array, fields, li.ref(), TRUE);
unknown's avatar
unknown committed
4006 4007 4008 4009 4010 4011 4012 4013 4014
}


table_map
Item_cond::used_tables() const
{						// This caches used_tables
  return used_tables_cache;
}

4015

unknown's avatar
unknown committed
4016 4017
void Item_cond::update_used_tables()
{
unknown's avatar
unknown committed
4018
  List_iterator_fast<Item> li(list);
unknown's avatar
unknown committed
4019
  Item *item;
4020 4021 4022

  used_tables_cache=0;
  const_item_cache=1;
unknown's avatar
unknown committed
4023 4024 4025
  while ((item=li++))
  {
    item->update_used_tables();
4026
    used_tables_cache|= item->used_tables();
unknown's avatar
unknown committed
4027
    const_item_cache&= item->const_item();
unknown's avatar
unknown committed
4028 4029 4030 4031 4032 4033 4034
  }
}


void Item_cond::print(String *str)
{
  str->append('(');
unknown's avatar
unknown committed
4035
  List_iterator_fast<Item> li(list);
unknown's avatar
unknown committed
4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048
  Item *item;
  if ((item=li++))
    item->print(str);
  while ((item=li++))
  {
    str->append(' ');
    str->append(func_name());
    str->append(' ');
    item->print(str);
  }
  str->append(')');
}

4049

4050
void Item_cond::neg_arguments(THD *thd)
4051 4052 4053 4054 4055
{
  List_iterator<Item> li(list);
  Item *item;
  while ((item= li++))		/* Apply not transformation to the arguments */
  {
4056 4057 4058
    Item *new_item= item->neg_transformer(thd);
    if (!new_item)
    {
unknown's avatar
unknown committed
4059 4060
      if (!(new_item= new Item_func_not(item)))
	return;					// Fatal OEM error
4061 4062
    }
    VOID(li.replace(new_item));
4063 4064 4065 4066
  }
}


4067
/*
unknown's avatar
unknown committed
4068
  Evaluation of AND(expr, expr, expr ...)
4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083

  NOTES:
    abort_if_null is set for AND expressions for which we don't care if the
    result is NULL or 0. This is set for:
    - WHERE clause
    - HAVING clause
    - IF(expression)

  RETURN VALUES
    1  If all expressions are true
    0  If all expressions are false or if we find a NULL expression and
       'abort_on_null' is set.
    NULL if all expression are either 1 or NULL
*/

unknown's avatar
unknown committed
4084 4085 4086

longlong Item_cond_and::val_int()
{
4087
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
4088
  List_iterator_fast<Item> li(list);
unknown's avatar
unknown committed
4089
  Item *item;
4090
  null_value= 0;
unknown's avatar
unknown committed
4091 4092
  while ((item=li++))
  {
unknown's avatar
unknown committed
4093
    if (!item->val_bool())
unknown's avatar
unknown committed
4094
    {
4095 4096
      if (abort_on_null || !(null_value= item->null_value))
	return 0;				// return FALSE
unknown's avatar
unknown committed
4097 4098
    }
  }
4099
  return null_value ? 0 : 1;
unknown's avatar
unknown committed
4100 4101
}

4102

unknown's avatar
unknown committed
4103 4104
longlong Item_cond_or::val_int()
{
4105
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
4106
  List_iterator_fast<Item> li(list);
unknown's avatar
unknown committed
4107 4108 4109 4110
  Item *item;
  null_value=0;
  while ((item=li++))
  {
unknown's avatar
unknown committed
4111
    if (item->val_bool())
unknown's avatar
unknown committed
4112 4113 4114 4115 4116 4117 4118 4119 4120 4121
    {
      null_value=0;
      return 1;
    }
    if (item->null_value)
      null_value=1;
  }
  return 0;
}

4122 4123 4124 4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145
/*
  Create an AND expression from two expressions

  SYNOPSIS
   and_expressions()
   a		expression or NULL
   b    	expression.
   org_item	Don't modify a if a == *org_item
		If a == NULL, org_item is set to point at b,
		to ensure that future calls will not modify b.

  NOTES
    This will not modify item pointed to by org_item or b
    The idea is that one can call this in a loop and create and
    'and' over all items without modifying any of the original items.

  RETURN
    NULL	Error
    Item
*/

Item *and_expressions(Item *a, Item *b, Item **org_item)
{
  if (!a)
4146
    return (*org_item= (Item*) b);
4147 4148 4149
  if (a == *org_item)
  {
    Item_cond *res;
4150
    if ((res= new Item_cond_and(a, (Item*) b)))
4151
    {
4152
      res->used_tables_cache= a->used_tables() | b->used_tables();
4153 4154
      res->not_null_tables_cache= a->not_null_tables() | b->not_null_tables();
    }
4155 4156
    return res;
  }
4157
  if (((Item_cond_and*) a)->add((Item*) b))
4158 4159
    return 0;
  ((Item_cond_and*) a)->used_tables_cache|= b->used_tables();
4160
  ((Item_cond_and*) a)->not_null_tables_cache|= b->not_null_tables();
4161 4162 4163 4164
  return a;
}


unknown's avatar
unknown committed
4165 4166
longlong Item_func_isnull::val_int()
{
4167
  DBUG_ASSERT(fixed == 1);
4168 4169 4170 4171
  /*
    Handle optimization if the argument can't be null
    This has to be here because of the test in update_used_tables().
  */
unknown's avatar
unknown committed
4172
  if (!used_tables_cache && !with_subselect)
unknown's avatar
unknown committed
4173
    return cached_value;
unknown's avatar
unknown committed
4174
  return args[0]->is_null() ? 1: 0;
unknown's avatar
unknown committed
4175 4176
}

4177 4178
longlong Item_is_not_null_test::val_int()
{
4179
  DBUG_ASSERT(fixed == 1);
4180
  DBUG_ENTER("Item_is_not_null_test::val_int");
unknown's avatar
unknown committed
4181
  if (!used_tables_cache && !with_subselect)
4182 4183
  {
    owner->was_null|= (!cached_value);
unknown's avatar
unknown committed
4184
    DBUG_PRINT("info", ("cached: %ld", (long) cached_value));
4185 4186 4187 4188
    DBUG_RETURN(cached_value);
  }
  if (args[0]->is_null())
  {
unknown's avatar
unknown committed
4189
    DBUG_PRINT("info", ("null"));
4190 4191 4192 4193 4194 4195 4196 4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207
    owner->was_null|= 1;
    DBUG_RETURN(0);
  }
  else
    DBUG_RETURN(1);
}

/* Optimize case of not_null_column IS NULL */
void Item_is_not_null_test::update_used_tables()
{
  if (!args[0]->maybe_null)
  {
    used_tables_cache= 0;			/* is always true */
    cached_value= (longlong) 1;
  }
  else
  {
    args[0]->update_used_tables();
unknown's avatar
unknown committed
4208
    if (!(used_tables_cache=args[0]->used_tables()) && !with_subselect)
4209 4210 4211 4212 4213 4214
    {
      /* Remember if the value is always NULL or never NULL */
      cached_value= (longlong) !args[0]->is_null();
    }
  }
}
4215

4216

unknown's avatar
unknown committed
4217 4218
longlong Item_func_isnotnull::val_int()
{
4219
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
4220
  return args[0]->is_null() ? 0 : 1;
unknown's avatar
unknown committed
4221 4222 4223
}


4224 4225 4226 4227
void Item_func_isnotnull::print(String *str)
{
  str->append('(');
  args[0]->print(str);
4228
  str->append(STRING_WITH_LEN(" is not null)"));
4229 4230 4231
}


unknown's avatar
unknown committed
4232 4233
longlong Item_func_like::val_int()
{
4234
  DBUG_ASSERT(fixed == 1);
4235
  String* res = args[0]->val_str(&tmp_value1);
unknown's avatar
unknown committed
4236 4237 4238 4239 4240
  if (args[0]->null_value)
  {
    null_value=1;
    return 0;
  }
4241
  String* res2 = args[1]->val_str(&tmp_value2);
unknown's avatar
unknown committed
4242 4243 4244 4245 4246 4247
  if (args[1]->null_value)
  {
    null_value=1;
    return 0;
  }
  null_value=0;
4248 4249
  if (canDoTurboBM)
    return turboBM_matches(res->ptr(), res->length()) ? 1 : 0;
4250
  return my_wildcmp(cmp.cmp_collation.collation,
4251 4252 4253
		    res->ptr(),res->ptr()+res->length(),
		    res2->ptr(),res2->ptr()+res2->length(),
		    escape,wild_one,wild_many) ? 0 : 1;
unknown's avatar
unknown committed
4254 4255 4256 4257 4258 4259 4260
}


/* We can optimize a where if first character isn't a wildcard */

Item_func::optimize_type Item_func_like::select_optimize() const
{
4261
  if (args[1]->const_item())
unknown's avatar
unknown committed
4262
  {
4263 4264 4265 4266 4267 4268
    String* res2= args[1]->val_str((String *)&tmp_value2);

    if (!res2)
      return OPTIMIZE_NONE;

    if (*res2->ptr() != wild_many)
unknown's avatar
unknown committed
4269
    {
4270
      if (args[0]->result_type() != STRING_RESULT || *res2->ptr() != wild_one)
unknown's avatar
unknown committed
4271 4272 4273 4274 4275 4276
	return OPTIMIZE_OP;
    }
  }
  return OPTIMIZE_NONE;
}

4277

4278
bool Item_func_like::fix_fields(THD *thd, Item **ref)
4279
{
4280
  DBUG_ASSERT(fixed == 0);
4281 4282
  if (Item_bool_func2::fix_fields(thd, ref) ||
      escape_item->fix_fields(thd, &escape_item))
unknown's avatar
unknown committed
4283
    return TRUE;
4284

4285
  if (!escape_item->const_during_execution())
4286
  {
4287
    my_error(ER_WRONG_ARGUMENTS,MYF(0),"ESCAPE");
unknown's avatar
unknown committed
4288
    return TRUE;
4289 4290 4291 4292 4293 4294
  }
  
  if (escape_item->const_item())
  {
    /* If we are on execution stage */
    String *escape_str= escape_item->val_str(&tmp_value1);
4295 4296
    if (escape_str)
    {
4297 4298 4299 4300 4301 4302 4303 4304 4305
      if (escape_used_in_parsing && (
             (((thd->variables.sql_mode & MODE_NO_BACKSLASH_ESCAPES) &&
                escape_str->numchars() != 1) ||
               escape_str->numchars() > 1)))
      {
        my_error(ER_WRONG_ARGUMENTS,MYF(0),"ESCAPE");
        return TRUE;
      }

unknown's avatar
unknown committed
4306
      if (use_mb(cmp.cmp_collation.collation))
4307
      {
4308
        CHARSET_INFO *cs= escape_str->charset();
4309 4310 4311 4312 4313 4314 4315 4316 4317
        my_wc_t wc;
        int rc= cs->cset->mb_wc(cs, &wc,
                                (const uchar*) escape_str->ptr(),
                                (const uchar*) escape_str->ptr() +
                                               escape_str->length());
        escape= (int) (rc > 0 ? wc : '\\');
      }
      else
      {
unknown's avatar
unknown committed
4318 4319 4320 4321 4322
        /*
          In the case of 8bit character set, we pass native
          code instead of Unicode code as "escape" argument.
          Convert to "cs" if charset of escape differs.
        */
unknown's avatar
unknown committed
4323
        CHARSET_INFO *cs= cmp.cmp_collation.collation;
unknown's avatar
unknown committed
4324 4325 4326 4327 4328 4329 4330 4331 4332 4333 4334 4335 4336
        uint32 unused;
        if (escape_str->needs_conversion(escape_str->length(),
                                         escape_str->charset(), cs, &unused))
        {
          char ch;
          uint errors;
          uint32 cnvlen= copy_and_convert(&ch, 1, cs, escape_str->ptr(),
                                          escape_str->length(),
                                          escape_str->charset(), &errors);
          escape= cnvlen ? ch : '\\';
        }
        else
          escape= *(escape_str->ptr());
4337 4338 4339 4340
      }
    }
    else
      escape= '\\';
unknown's avatar
unknown committed
4341

4342
    /*
4343 4344
      We could also do boyer-more for non-const items, but as we would have to
      recompute the tables for each row it's not worth it.
4345
    */
4346 4347
    if (args[1]->const_item() && !use_strnxfrm(collation.collation) &&
       !(specialflag & SPECIAL_NO_NEW_FUNC))
4348
    {
4349 4350
      String* res2 = args[1]->val_str(&tmp_value2);
      if (!res2)
unknown's avatar
unknown committed
4351
        return FALSE;				// Null argument
4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362 4363 4364 4365 4366 4367 4368 4369 4370 4371
      
      const size_t len   = res2->length();
      const char*  first = res2->ptr();
      const char*  last  = first + len - 1;
      /*
        len must be > 2 ('%pattern%')
        heuristic: only do TurboBM for pattern_len > 2
      */
      
      if (len > MIN_TURBOBM_PATTERN_LEN + 2 &&
          *first == wild_many &&
          *last  == wild_many)
      {
        const char* tmp = first + 1;
        for (; *tmp != wild_many && *tmp != wild_one && *tmp != escape; tmp++) ;
        canDoTurboBM = (tmp == last) && !use_mb(args[0]->collation.collation);
      }
      if (canDoTurboBM)
      {
        pattern     = first + 1;
4372
        pattern_len = (int) len - 2;
4373
        DBUG_PRINT("info", ("Initializing pattern: '%s'", first));
4374 4375 4376
        int *suff = (int*) thd->alloc((int) (sizeof(int)*
                                      ((pattern_len + 1)*2+
                                      alphabet_size)));
4377 4378 4379 4380 4381 4382
        bmGs      = suff + pattern_len + 1;
        bmBc      = bmGs + pattern_len + 1;
        turboBM_compute_good_suffix_shifts(suff);
        turboBM_compute_bad_character_shifts();
        DBUG_PRINT("info",("done"));
      }
4383 4384
    }
  }
unknown's avatar
unknown committed
4385
  return FALSE;
4386 4387
}

4388 4389 4390 4391 4392 4393
void Item_func_like::cleanup()
{
  canDoTurboBM= FALSE;
  Item_bool_func2::cleanup();
}

unknown's avatar
unknown committed
4394 4395 4396
#ifdef USE_REGEX

bool
4397
Item_func_regex::fix_fields(THD *thd, Item **ref)
unknown's avatar
unknown committed
4398
{
4399
  DBUG_ASSERT(fixed == 0);
unknown's avatar
unknown committed
4400
  if ((!args[0]->fixed &&
4401
       args[0]->fix_fields(thd, args)) || args[0]->check_cols(1) ||
unknown's avatar
unknown committed
4402
      (!args[1]->fixed &&
4403
       args[1]->fix_fields(thd, args + 1)) || args[1]->check_cols(1))
unknown's avatar
unknown committed
4404
    return TRUE;				/* purecov: inspected */
unknown's avatar
unknown committed
4405
  with_sum_func=args[0]->with_sum_func || args[1]->with_sum_func;
unknown's avatar
unknown committed
4406 4407
  max_length= 1;
  decimals= 0;
4408

4409
  if (agg_arg_charsets(cmp_collation, args, 2, MY_COLL_CMP_CONV, 1))
unknown's avatar
unknown committed
4410
    return TRUE;
4411

unknown's avatar
unknown committed
4412
  used_tables_cache=args[0]->used_tables() | args[1]->used_tables();
4413 4414
  not_null_tables_cache= (args[0]->not_null_tables() |
			  args[1]->not_null_tables());
unknown's avatar
unknown committed
4415 4416 4417 4418
  const_item_cache=args[0]->const_item() && args[1]->const_item();
  if (!regex_compiled && args[1]->const_item())
  {
    char buff[MAX_FIELD_WIDTH];
4419
    String tmp(buff,sizeof(buff),&my_charset_bin);
unknown's avatar
unknown committed
4420 4421 4422 4423
    String *res=args[1]->val_str(&tmp);
    if (args[1]->null_value)
    {						// Will always return NULL
      maybe_null=1;
4424
      fixed= 1;
unknown's avatar
unknown committed
4425
      return FALSE;
unknown's avatar
unknown committed
4426 4427
    }
    int error;
unknown's avatar
unknown committed
4428 4429 4430 4431 4432 4433
    if ((error= my_regcomp(&preg,res->c_ptr(),
                           ((cmp_collation.collation->state &
                             (MY_CS_BINSORT | MY_CS_CSSORT)) ?
                            REG_EXTENDED | REG_NOSUB :
                            REG_EXTENDED | REG_NOSUB | REG_ICASE),
                           cmp_collation.collation)))
unknown's avatar
unknown committed
4434
    {
unknown's avatar
unknown committed
4435
      (void) my_regerror(error,&preg,buff,sizeof(buff));
4436
      my_error(ER_REGEXP_ERROR, MYF(0), buff);
unknown's avatar
unknown committed
4437
      return TRUE;
unknown's avatar
unknown committed
4438 4439 4440 4441 4442 4443
    }
    regex_compiled=regex_is_const=1;
    maybe_null=args[0]->maybe_null;
  }
  else
    maybe_null=1;
4444
  fixed= 1;
unknown's avatar
unknown committed
4445
  return FALSE;
unknown's avatar
unknown committed
4446 4447
}

4448

unknown's avatar
unknown committed
4449 4450
longlong Item_func_regex::val_int()
{
4451
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
4452
  char buff[MAX_FIELD_WIDTH];
4453
  String *res, tmp(buff,sizeof(buff),&my_charset_bin);
unknown's avatar
unknown committed
4454 4455 4456 4457 4458 4459 4460 4461 4462 4463

  res=args[0]->val_str(&tmp);
  if (args[0]->null_value)
  {
    null_value=1;
    return 0;
  }
  if (!regex_is_const)
  {
    char buff2[MAX_FIELD_WIDTH];
4464
    String *res2, tmp2(buff2,sizeof(buff2),&my_charset_bin);
unknown's avatar
unknown committed
4465 4466 4467 4468 4469 4470 4471

    res2= args[1]->val_str(&tmp2);
    if (args[1]->null_value)
    {
      null_value=1;
      return 0;
    }
unknown's avatar
unknown committed
4472
    if (!regex_compiled || stringcmp(res2,&prev_regexp))
unknown's avatar
unknown committed
4473 4474 4475 4476
    {
      prev_regexp.copy(*res2);
      if (regex_compiled)
      {
unknown's avatar
unknown committed
4477
	my_regfree(&preg);
unknown's avatar
unknown committed
4478 4479
	regex_compiled=0;
      }
unknown's avatar
Merge  
unknown committed
4480
      if (my_regcomp(&preg,res2->c_ptr_safe(),
unknown's avatar
unknown committed
4481 4482 4483 4484 4485
                     ((cmp_collation.collation->state &
                       (MY_CS_BINSORT | MY_CS_CSSORT)) ?
                      REG_EXTENDED | REG_NOSUB :
                      REG_EXTENDED | REG_NOSUB | REG_ICASE),
                     cmp_collation.collation))
unknown's avatar
unknown committed
4486 4487 4488 4489 4490 4491 4492 4493
      {
	null_value=1;
	return 0;
      }
      regex_compiled=1;
    }
  }
  null_value=0;
4494
  return my_regexec(&preg,res->c_ptr_safe(),0,(my_regmatch_t*) 0,0) ? 0 : 1;
unknown's avatar
unknown committed
4495 4496 4497
}


4498
void Item_func_regex::cleanup()
unknown's avatar
unknown committed
4499
{
4500 4501
  DBUG_ENTER("Item_func_regex::cleanup");
  Item_bool_func::cleanup();
unknown's avatar
unknown committed
4502 4503
  if (regex_compiled)
  {
unknown's avatar
unknown committed
4504
    my_regfree(&preg);
unknown's avatar
unknown committed
4505 4506
    regex_compiled=0;
  }
4507
  DBUG_VOID_RETURN;
unknown's avatar
unknown committed
4508 4509
}

4510

unknown's avatar
unknown committed
4511
#endif /* USE_REGEX */
4512 4513 4514


#ifdef LIKE_CMP_TOUPPER
unknown's avatar
unknown committed
4515
#define likeconv(cs,A) (uchar) (cs)->toupper(A)
4516
#else
unknown's avatar
unknown committed
4517
#define likeconv(cs,A) (uchar) (cs)->sort_order[(uchar) (A)]
4518 4519 4520 4521 4522 4523 4524 4525
#endif


/**********************************************************************
  turboBM_compute_suffixes()
  Precomputation dependent only on pattern_len.
**********************************************************************/

4526
void Item_func_like::turboBM_compute_suffixes(int *suff)
4527 4528 4529 4530
{
  const int   plm1 = pattern_len - 1;
  int            f = 0;
  int            g = plm1;
unknown's avatar
unknown committed
4531
  int *const splm1 = suff + plm1;
4532
  CHARSET_INFO	*cs= cmp.cmp_collation.collation;
4533 4534 4535

  *splm1 = pattern_len;

unknown's avatar
unknown committed
4536
  if (!cs->sort_order)
4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567
  {
    int i;
    for (i = pattern_len - 2; i >= 0; i--)
    {
      int tmp = *(splm1 + i - f);
      if (g < i && tmp < i - g)
	suff[i] = tmp;
      else
      {
	if (i < g)
	  g = i; // g = min(i, g)
	f = i;
	while (g >= 0 && pattern[g] == pattern[g + plm1 - f])
	  g--;
	suff[i] = f - g;
      }
    }
  }
  else
  {
    int i;
    for (i = pattern_len - 2; 0 <= i; --i)
    {
      int tmp = *(splm1 + i - f);
      if (g < i && tmp < i - g)
	suff[i] = tmp;
      else
      {
	if (i < g)
	  g = i; // g = min(i, g)
	f = i;
4568
	while (g >= 0 &&
unknown's avatar
unknown committed
4569
	       likeconv(cs, pattern[g]) == likeconv(cs, pattern[g + plm1 - f]))
4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582
	  g--;
	suff[i] = f - g;
      }
    }
  }
}


/**********************************************************************
   turboBM_compute_good_suffix_shifts()
   Precomputation dependent only on pattern_len.
**********************************************************************/

4583
void Item_func_like::turboBM_compute_good_suffix_shifts(int *suff)
4584 4585 4586
{
  turboBM_compute_suffixes(suff);

4587 4588
  int *end = bmGs + pattern_len;
  int *k;
4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601
  for (k = bmGs; k < end; k++)
    *k = pattern_len;

  int tmp;
  int i;
  int j          = 0;
  const int plm1 = pattern_len - 1;
  for (i = plm1; i > -1; i--)
  {
    if (suff[i] == i + 1)
    {
      for (tmp = plm1 - i; j < tmp; j++)
      {
4602
	int *tmp2 = bmGs + j;
4603 4604 4605 4606 4607 4608
	if (*tmp2 == pattern_len)
	  *tmp2 = tmp;
      }
    }
  }

4609
  int *tmp2;
4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629
  for (tmp = plm1 - i; j < tmp; j++)
  {
    tmp2 = bmGs + j;
    if (*tmp2 == pattern_len)
      *tmp2 = tmp;
  }

  tmp2 = bmGs + plm1;
  for (i = 0; i <= pattern_len - 2; i++)
    *(tmp2 - suff[i]) = plm1 - i;
}


/**********************************************************************
   turboBM_compute_bad_character_shifts()
   Precomputation dependent on pattern_len.
**********************************************************************/

void Item_func_like::turboBM_compute_bad_character_shifts()
{
unknown's avatar
unknown committed
4630 4631 4632 4633
  int *i;
  int *end = bmBc + alphabet_size;
  int j;
  const int plm1 = pattern_len - 1;
4634
  CHARSET_INFO	*cs= cmp.cmp_collation.collation;
unknown's avatar
unknown committed
4635

4636 4637 4638
  for (i = bmBc; i < end; i++)
    *i = pattern_len;

unknown's avatar
unknown committed
4639
  if (!cs->sort_order)
unknown's avatar
unknown committed
4640
  {
4641
    for (j = 0; j < plm1; j++)
4642
      bmBc[(uint) (uchar) pattern[j]] = plm1 - j;
unknown's avatar
unknown committed
4643
  }
4644
  else
unknown's avatar
unknown committed
4645
  {
4646
    for (j = 0; j < plm1; j++)
unknown's avatar
unknown committed
4647
      bmBc[(uint) likeconv(cs,pattern[j])] = plm1 - j;
unknown's avatar
unknown committed
4648
  }
4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659 4660 4661 4662 4663
}


/**********************************************************************
  turboBM_matches()
  Search for pattern in text, returns true/false for match/no match
**********************************************************************/

bool Item_func_like::turboBM_matches(const char* text, int text_len) const
{
  register int bcShift;
  register int turboShift;
  int shift = pattern_len;
  int j     = 0;
  int u     = 0;
4664
  CHARSET_INFO	*cs= cmp.cmp_collation.collation;
4665

4666 4667
  const int plm1=  pattern_len - 1;
  const int tlmpl= text_len - pattern_len;
4668 4669

  /* Searching */
unknown's avatar
unknown committed
4670
  if (!cs->sort_order)
4671 4672 4673
  {
    while (j <= tlmpl)
    {
4674
      register int i= plm1;
4675 4676 4677 4678
      while (i >= 0 && pattern[i] == text[i + j])
      {
	i--;
	if (i == plm1 - shift)
4679
	  i-= u;
4680 4681
      }
      if (i < 0)
unknown's avatar
unknown committed
4682
	return 1;
4683 4684 4685

      register const int v = plm1 - i;
      turboShift = u - v;
4686
      bcShift    = bmBc[(uint) (uchar) text[i + j]] - plm1 + i;
4687 4688 4689 4690 4691 4692 4693 4694 4695 4696
      shift      = max(turboShift, bcShift);
      shift      = max(shift, bmGs[i]);
      if (shift == bmGs[i])
	u = min(pattern_len - shift, v);
      else
      {
	if (turboShift < bcShift)
	  shift = max(shift, u + 1);
	u = 0;
      }
4697
      j+= shift;
4698
    }
unknown's avatar
unknown committed
4699
    return 0;
4700 4701 4702 4703 4704 4705
  }
  else
  {
    while (j <= tlmpl)
    {
      register int i = plm1;
unknown's avatar
unknown committed
4706
      while (i >= 0 && likeconv(cs,pattern[i]) == likeconv(cs,text[i + j]))
4707 4708 4709
      {
	i--;
	if (i == plm1 - shift)
4710
	  i-= u;
4711 4712
      }
      if (i < 0)
unknown's avatar
unknown committed
4713
	return 1;
4714 4715 4716

      register const int v = plm1 - i;
      turboShift = u - v;
unknown's avatar
unknown committed
4717
      bcShift    = bmBc[(uint) likeconv(cs, text[i + j])] - plm1 + i;
4718 4719 4720 4721 4722 4723 4724 4725 4726 4727
      shift      = max(turboShift, bcShift);
      shift      = max(shift, bmGs[i]);
      if (shift == bmGs[i])
	u = min(pattern_len - shift, v);
      else
      {
	if (turboShift < bcShift)
	  shift = max(shift, u + 1);
	u = 0;
      }
4728
      j+= shift;
4729
    }
unknown's avatar
unknown committed
4730
    return 0;
4731 4732
  }
}
unknown's avatar
unknown committed
4733

4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754

/*
  Make a logical XOR of the arguments.

  SYNOPSIS
    val_int()

  DESCRIPTION
  If either operator is NULL, return NULL.

  NOTE
    As we don't do any index optimization on XOR this is not going to be
    very fast to use.

  TODO (low priority)
    Change this to be optimized as:
      A XOR B   ->  (A) == 1 AND (B) <> 1) OR (A <> 1 AND (B) == 1)
    To be able to do this, we would however first have to extend the MySQL
    range optimizer to handle OR better.
*/

unknown's avatar
unknown committed
4755 4756
longlong Item_cond_xor::val_int()
{
4757
  DBUG_ASSERT(fixed == 1);
unknown's avatar
unknown committed
4758 4759 4760
  List_iterator<Item> li(list);
  Item *item;
  int result=0;	
4761
  null_value=0;
unknown's avatar
unknown committed
4762 4763
  while ((item=li++))
  {
4764 4765 4766 4767 4768 4769
    result^= (item->val_int() != 0);
    if (item->null_value)
    {
      null_value=1;
      return 0;
    }
unknown's avatar
unknown committed
4770
  }
4771
  return (longlong) result;
unknown's avatar
unknown committed
4772
}
4773 4774 4775 4776

/*
  Apply NOT transformation to the item and return a new one.

unknown's avatar
unknown committed
4777
  SYNOPSIS
4778
    neg_transformer()
4779
    thd		thread handler
4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799

  DESCRIPTION
    Transform the item using next rules:
       a AND b AND ...    -> NOT(a) OR NOT(b) OR ...
       a OR b OR ...      -> NOT(a) AND NOT(b) AND ...
       NOT(a)             -> a
       a = b              -> a != b
       a != b             -> a = b
       a < b              -> a >= b
       a >= b             -> a < b
       a > b              -> a <= b
       a <= b             -> a > b
       IS NULL(a)         -> IS NOT NULL(a)
       IS NOT NULL(a)     -> IS NULL(a)

  RETURN
    New item or
    NULL if we cannot apply NOT transformation (see Item::neg_transformer()).
*/

4800
Item *Item_func_not::neg_transformer(THD *thd)	/* NOT(x)  ->  x */
4801
{
unknown's avatar
unknown committed
4802
  return args[0];
4803 4804
}

4805 4806

Item *Item_bool_rowready_func2::neg_transformer(THD *thd)
4807
{
4808 4809
  Item *item= negated_item();
  return item;
4810 4811
}

4812 4813 4814

/* a IS NULL  ->  a IS NOT NULL */
Item *Item_func_isnull::neg_transformer(THD *thd)
4815
{
4816 4817
  Item *item= new Item_func_isnotnull(args[0]);
  return item;
4818 4819
}

4820 4821 4822

/* a IS NOT NULL  ->  a IS NULL */
Item *Item_func_isnotnull::neg_transformer(THD *thd)
4823
{
4824 4825
  Item *item= new Item_func_isnull(args[0]);
  return item;
4826 4827
}

4828 4829 4830

Item *Item_cond_and::neg_transformer(THD *thd)	/* NOT(a AND b AND ...)  -> */
					/* NOT a OR NOT b OR ... */
4831
{
4832 4833 4834
  neg_arguments(thd);
  Item *item= new Item_cond_or(list);
  return item;
4835 4836
}

4837 4838 4839

Item *Item_cond_or::neg_transformer(THD *thd)	/* NOT(a OR b OR ...)  -> */
					/* NOT a AND NOT b AND ... */
4840
{
4841 4842 4843
  neg_arguments(thd);
  Item *item= new Item_cond_and(list);
  return item;
4844 4845
}

4846

4847 4848 4849 4850 4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861 4862 4863 4864 4865 4866 4867 4868
Item *Item_func_nop_all::neg_transformer(THD *thd)
{
  /* "NOT (e $cmp$ ANY (SELECT ...)) -> e $rev_cmp$" ALL (SELECT ...) */
  Item_func_not_all *new_item= new Item_func_not_all(args[0]);
  Item_allany_subselect *allany= (Item_allany_subselect*)args[0];
  allany->func= allany->func_creator(FALSE);
  allany->all= !allany->all;
  allany->upper_item= new_item;
  return new_item;
}

Item *Item_func_not_all::neg_transformer(THD *thd)
{
  /* "NOT (e $cmp$ ALL (SELECT ...)) -> e $rev_cmp$" ANY (SELECT ...) */
  Item_func_nop_all *new_item= new Item_func_nop_all(args[0]);
  Item_allany_subselect *allany= (Item_allany_subselect*)args[0];
  allany->all= !allany->all;
  allany->func= allany->func_creator(TRUE);
  allany->upper_item= new_item;
  return new_item;
}

4869
Item *Item_func_eq::negated_item()		/* a = b  ->  a != b */
4870
{
4871
  return new Item_func_ne(args[0], args[1]);
4872 4873
}

4874 4875

Item *Item_func_ne::negated_item()		/* a != b  ->  a = b */
4876
{
4877
  return new Item_func_eq(args[0], args[1]);
4878 4879
}

4880 4881

Item *Item_func_lt::negated_item()		/* a < b  ->  a >= b */
4882
{
4883
  return new Item_func_ge(args[0], args[1]);
4884 4885
}

4886 4887

Item *Item_func_ge::negated_item()		/* a >= b  ->  a < b */
4888
{
4889
  return new Item_func_lt(args[0], args[1]);
4890 4891
}

4892 4893

Item *Item_func_gt::negated_item()		/* a > b  ->  a <= b */
4894
{
4895
  return new Item_func_le(args[0], args[1]);
4896 4897
}

4898 4899

Item *Item_func_le::negated_item()		/* a <= b  ->  a > b */
4900
{
4901
  return new Item_func_gt(args[0], args[1]);
4902 4903
}

4904 4905
// just fake method, should never be called
Item *Item_bool_rowready_func2::negated_item()
4906
{
4907 4908
  DBUG_ASSERT(0);
  return 0;
4909
}
4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926

Item_equal::Item_equal(Item_field *f1, Item_field *f2)
  : Item_bool_func(), const_item(0), eval_item(0), cond_false(0)
{
  const_item_cache= 0;
  fields.push_back(f1);
  fields.push_back(f2);
}

Item_equal::Item_equal(Item *c, Item_field *f)
  : Item_bool_func(), eval_item(0), cond_false(0)
{
  const_item_cache= 0;
  fields.push_back(f);
  const_item= c;
}

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
Item_equal::Item_equal(Item_equal *item_equal)
  : Item_bool_func(), eval_item(0), cond_false(0)
{
  const_item_cache= 0;
  List_iterator_fast<Item_field> li(item_equal->fields);
  Item_field *item;
  while ((item= li++))
  {
    fields.push_back(item);
  }
  const_item= item_equal->const_item;
  cond_false= item_equal->cond_false;
}

void Item_equal::add(Item *c)
{
  if (cond_false)
    return;
  if (!const_item)
  {
    const_item= c;
    return;
  }
  Item_func_eq *func= new Item_func_eq(c, const_item);
  func->set_cmp_func();
unknown's avatar
unknown committed
4953
  func->quick_fix_field();
unknown's avatar
unknown committed
4954 4955
  if ((cond_false= !func->val_int()))
    const_item_cache= 1;
4956 4957 4958 4959 4960 4961 4962
}

void Item_equal::add(Item_field *f)
{
  fields.push_back(f);
}

unknown's avatar
unknown committed
4963 4964
uint Item_equal::members()
{
4965
  return fields.elements;
unknown's avatar
unknown committed
4966 4967 4968 4969 4970 4971 4972 4973
}


/*
  Check whether a field is referred in the multiple equality 

  SYNOPSIS
    contains()
unknown's avatar
unknown committed
4974
    field   field whose occurrence is to be checked
unknown's avatar
unknown committed
4975 4976
  
  DESCRIPTION
unknown's avatar
unknown committed
4977
    The function checks whether field is occurred in the Item_equal object 
unknown's avatar
unknown committed
4978 4979 4980 4981 4982 4983
    
  RETURN VALUES
    1       if nultiple equality contains a reference to field
    0       otherwise    
*/

4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 4994 4995
bool Item_equal::contains(Field *field)
{
  List_iterator_fast<Item_field> it(fields);
  Item_field *item;
  while ((item= it++))
  {
    if (field->eq(item->field))
        return 1;
  }
  return 0;
}

unknown's avatar
unknown committed
4996 4997 4998 4999 5000 5001 5002 5003 5004

/*
  Join members of another Item_equal object  

  SYNOPSIS
    merge()
    item    multiple equality whose members are to be joined
  
  DESCRIPTION
unknown's avatar
unknown committed
5005
    The function actually merges two multiple equalities.
unknown's avatar
unknown committed
5006 5007 5008 5009 5010 5011 5012 5013 5014
    After this operation the Item_equal object additionally contains
    the field items of another item of the type Item_equal.
    If the optional constant items are not equal the cond_false flag is
    set to 1.  
       
  RETURN VALUES
    none    
*/

5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025
void Item_equal::merge(Item_equal *item)
{
  fields.concat(&item->fields);
  Item *c= item->const_item;
  if (c)
  {
    /* 
      The flag cond_false will be set to 1 after this, if 
      the multiple equality already contains a constant and its 
      value is  not equal to the value of c.
    */
unknown's avatar
unknown committed
5026
    add(c);
5027 5028 5029 5030
  }
  cond_false|= item->cond_false;
} 

unknown's avatar
unknown committed
5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056

/*
  Order field items in multiple equality according to a sorting criteria 

  SYNOPSIS
    sort()
    cmp          function to compare field item 
    arg          context extra parameter for the cmp function
  
  DESCRIPTION
    The function perform ordering of the field items in the Item_equal
    object according to the criteria determined by the cmp callback parameter.
    If cmp(item_field1,item_field2,arg)<0 than item_field1 must be
    placed after item_fiel2.

  IMPLEMENTATION
    The function sorts field items by the exchange sort algorithm.
    The list of field items is looked through and whenever two neighboring
    members follow in a wrong order they are swapped. This is performed
    again and again until we get all members in a right order.
         
  RETURN VALUES
    None    
*/

void Item_equal::sort(Item_field_cmpfunc cmp, void *arg)
5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068
{
  bool swap;
  List_iterator<Item_field> it(fields);
  do
  {
    Item_field *item1= it++;
    Item_field **ref1= it.ref();
    Item_field *item2;

    swap= FALSE;
    while ((item2= it++))
    {
unknown's avatar
unknown committed
5069 5070
      Item_field **ref2= it.ref();
      if (cmp(item1, item2, arg) < 0)
5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086
      {
        Item_field *item= *ref1;
        *ref1= *ref2;
        *ref2= item;
        swap= TRUE;
      }
      else
      {
        item1= item2;
        ref1= ref2;
      }
    }
    it.rewind();
  } while (swap);
}

unknown's avatar
unknown committed
5087 5088 5089 5090 5091

/*
  Check appearance of new constant items in the multiple equality object

  SYNOPSIS
5092
    update_const()
unknown's avatar
unknown committed
5093 5094 5095 5096 5097 5098 5099 5100 5101 5102 5103 5104
  
  DESCRIPTION
    The function checks appearance of new constant items among
    the members of multiple equalities. Each new constant item is
    compared with the designated constant item if there is any in the
    multiple equality. If there is none the first new constant item
    becomes designated.
      
  RETURN VALUES
    none    
*/

5105
void Item_equal::update_const()
unknown's avatar
unknown committed
5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118
{
  List_iterator<Item_field> it(fields);
  Item *item;
  while ((item= it++))
  {
    if (item->const_item())
    {
      it.remove();
      add(item);
    }
  }
}

5119
bool Item_equal::fix_fields(THD *thd, Item **ref)
5120 5121 5122 5123 5124
{
  List_iterator_fast<Item_field> li(fields);
  Item *item;
  not_null_tables_cache= used_tables_cache= 0;
  const_item_cache= 0;
unknown's avatar
unknown committed
5125
  while ((item= li++))
5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138 5139 5140 5141 5142 5143
  {
    table_map tmp_table_map;
    used_tables_cache|= item->used_tables();
    tmp_table_map= item->not_null_tables();
    not_null_tables_cache|= tmp_table_map;
    if (item->maybe_null)
      maybe_null=1;
  }
  fix_length_and_dec();
  fixed= 1;
  return 0;
}

void Item_equal::update_used_tables()
{
  List_iterator_fast<Item_field> li(fields);
  Item *item;
  not_null_tables_cache= used_tables_cache= 0;
unknown's avatar
unknown committed
5144 5145
  if ((const_item_cache= cond_false))
    return;
5146 5147 5148 5149 5150 5151 5152 5153 5154 5155
  while ((item=li++))
  {
    item->update_used_tables();
    used_tables_cache|= item->used_tables();
    const_item_cache&= item->const_item();
  }
}

longlong Item_equal::val_int()
{
5156
  Item_field *item_field;
5157 5158 5159 5160 5161 5162 5163
  if (cond_false)
    return 0;
  List_iterator_fast<Item_field> it(fields);
  Item *item= const_item ? const_item : it++;
  if ((null_value= item->null_value))
    return 0;
  eval_item->store_value(item);
5164
  while ((item_field= it++))
5165
  {
5166 5167 5168 5169 5170 5171
    /* Skip fields of non-const tables. They haven't been read yet */
    if (item_field->field->table->const_table)
    {
      if ((null_value= item_field->null_value) || eval_item->cmp(item_field))
        return 0;
    }
5172 5173 5174 5175 5176 5177
  }
  return 1;
}

void Item_equal::fix_length_and_dec()
{
unknown's avatar
unknown committed
5178
  Item *item= get_first();
unknown's avatar
unknown committed
5179 5180
  eval_item= cmp_item::get_comparator(item->result_type(),
                                      item->collation.collation);
5181 5182
}

5183
bool Item_equal::walk(Item_processor processor, bool walk_subquery, uchar *arg)
5184 5185 5186 5187
{
  List_iterator_fast<Item_field> it(fields);
  Item *item;
  while ((item= it++))
5188 5189
  {
    if (item->walk(processor, walk_subquery, arg))
5190
      return 1;
5191 5192
  }
  return Item_func::walk(processor, walk_subquery, arg);
5193 5194
}

5195
Item *Item_equal::transform(Item_transformer transformer, uchar *arg)
5196
{
5197 5198
  DBUG_ASSERT(!current_thd->is_stmt_prepare());

5199 5200 5201 5202
  List_iterator<Item_field> it(fields);
  Item *item;
  while ((item= it++))
  {
unknown's avatar
unknown committed
5203
    Item *new_item= item->transform(transformer, arg);
5204 5205
    if (!new_item)
      return 0;
5206 5207 5208 5209 5210 5211 5212

    /*
      THD::change_item_tree() should be called only if the tree was
      really transformed, i.e. when a new item has been created.
      Otherwise we'll be allocating a lot of unnecessary memory for
      change records at each execution.
    */
5213
    if (new_item != item)
5214
      current_thd->change_item_tree((Item **) it.ref(), new_item);
5215
  }
unknown's avatar
unknown committed
5216
  return Item_func::transform(transformer, arg);
5217 5218 5219 5220 5221 5222 5223 5224
}

void Item_equal::print(String *str)
{
  str->append(func_name());
  str->append('(');
  List_iterator_fast<Item_field> it(fields);
  Item *item;
unknown's avatar
unknown committed
5225 5226 5227 5228 5229
  if (const_item)
    const_item->print(str);
  else
  {
    item= it++;
5230
    item->print(str);
unknown's avatar
unknown committed
5231
  }
5232 5233 5234 5235 5236 5237 5238 5239 5240
  while ((item= it++))
  {
    str->append(',');
    str->append(' ');
    item->print(str);
  }
  str->append(')');
}