Merge bk-internal:/home/bk/mysql-5.1-opt

into  dl145s.mysql.com:/data/bk/team_tree_merge/MERGE/mysql-5.1-opt


sql/item.cc:
  Auto merged
sql/opt_range.cc:
  Auto merged

mysql-test/r/func_in.result

@@ -343,3 +343,71 @@ some_id
 1
 2
 drop table t1;
+create table t1(f1 char(1));
+insert into t1 values ('a'),('b'),('1');
+select f1 from t1 where f1 in ('a',1);
+f1
+a
+1
+select f1, case f1 when 'a' then '+' when 1 then '-' end from t1;
+f1	case f1 when 'a' then '+' when 1 then '-' end
+a	+
+b	NULL
+1	-
+create index t1f1_idx on t1(f1);
+select f1 from t1 where f1 in ('a',1);
+f1
+1
+a
+explain select f1 from t1 where f1 in ('a',1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	index	NULL	t1f1_idx	2	NULL	3	Using where; Using index
+select f1 from t1 where f1 in ('a','b');
+f1
+a
+b
+explain select f1 from t1 where f1 in ('a','b');
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	index	t1f1_idx	t1f1_idx	2	NULL	3	Using where; Using index
+select f1 from t1 where f1 in (2,1);
+f1
+1
+explain select f1 from t1 where f1 in (2,1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	index	t1f1_idx	t1f1_idx	2	NULL	3	Using where; Using index
+create table t2(f2 int, index t2f2(f2));
+insert into t2 values(0),(1),(2);
+select f2 from t2 where f2 in ('a',2);
+f2
+0
+2
+Warnings:
+Warning	1292	Truncated incorrect DOUBLE value: 'a'
+Warning	1292	Truncated incorrect DOUBLE value: 'a'
+Warning	1292	Truncated incorrect DOUBLE value: 'a'
+explain select f2 from t2 where f2 in ('a',2);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	NULL	t2f2	5	NULL	3	Using where; Using index
+select f2 from t2 where f2 in ('a','b');
+f2
+0
+Warnings:
+Warning	1292	Truncated incorrect DOUBLE value: 'a'
+Warning	1292	Truncated incorrect DOUBLE value: 'b'
+explain select f2 from t2 where f2 in ('a','b');
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	t2f2	t2f2	5	NULL	3	Using where; Using index
+Warnings:
+Warning	1292	Truncated incorrect DOUBLE value: 'a'
+Warning	1292	Truncated incorrect DOUBLE value: 'b'
+select f2 from t2 where f2 in (1,'b');
+f2
+0
+1
+Warnings:
+Warning	1292	Truncated incorrect DOUBLE value: 'b'
+Warning	1292	Truncated incorrect DOUBLE value: 'b'
+explain select f2 from t2 where f2 in (1,'b');
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	NULL	t2f2	5	NULL	3	Using where; Using index
+drop table t1, t2;

mysql-test/t/func_in.test

@@ -232,3 +232,27 @@ select some_id from t1 where some_id not in(2,-1);
 select some_id from t1 where some_id not in(-4,-1,-4);
 select some_id from t1 where some_id not in(-4,-1,3423534,2342342);
 drop table t1;
+
+#
+# Bug#18360: Type aggregation for IN and CASE may lead to a wrong result 
+#
+create table t1(f1 char(1));
+insert into t1 values ('a'),('b'),('1');
+select f1 from t1 where f1 in ('a',1);
+select f1, case f1 when 'a' then '+' when 1 then '-' end from t1;
+create index t1f1_idx on t1(f1);
+select f1 from t1 where f1 in ('a',1);
+explain select f1 from t1 where f1 in ('a',1);
+select f1 from t1 where f1 in ('a','b');
+explain select f1 from t1 where f1 in ('a','b');
+select f1 from t1 where f1 in (2,1);
+explain select f1 from t1 where f1 in (2,1);
+create table t2(f2 int, index t2f2(f2));
+insert into t2 values(0),(1),(2);
+select f2 from t2 where f2 in ('a',2);
+explain select f2 from t2 where f2 in ('a',2);
+select f2 from t2 where f2 in ('a','b');
+explain select f2 from t2 where f2 in ('a','b');
+select f2 from t2 where f2 in (1,'b');
+explain select f2 from t2 where f2 in (1,'b');
+drop table t1, t2;

mysql-test/t/view.test

@@ -2443,7 +2443,7 @@ DROP TABLE t1, t2;
 #
 # Bug #16069: VIEW does return the same results as underlying SELECT
 #             with WHERE condition containing BETWEEN over dates 
-
+# Dates as strings should be casted to date type
 CREATE TABLE t1 (id int NOT NULL PRIMARY KEY,
                  td date DEFAULT NULL, KEY idx(td));
 

sql/item.cc

@@ -5711,11 +5711,6 @@ void Item_trigger_field::cleanup()
 }
 
 
-/*
-  If item is a const function, calculate it and return a const item
-  The original item is freed if not returned
-*/
-
 Item_result item_cmp_type(Item_result a,Item_result b)
 {
   if (a == STRING_RESULT && b == STRING_RESULT)

sql/item_cmpfunc.cc

@@ -66,12 +66,10 @@ static void agg_result_type(Item_result *type, Item **items, uint nitems)
 /*
   Aggregates result types from the array of items.
 
-  SYNOPSIS:
+  SYNOPSIS
     agg_cmp_type()
-    thd          thread handle
-    type   [out] the aggregated type
-    items        array of items to aggregate the type from
-    nitems       number of items in the array
+      items        array of items to aggregate the type from
+      nitems       number of items in the array
 
   DESCRIPTION
     This function aggregates result types from the array of items. Found type
@@ -79,12 +77,43 @@ static void agg_result_type(Item_result *type, Item **items, uint nitems)
     Aggregation itself is performed by the item_cmp_type() function.
 */
 
-static void agg_cmp_type(THD *thd, Item_result *type, Item **items, uint nitems)
+static Item_result agg_cmp_type(Item **items, uint nitems)
 {
   uint i;
-  type[0]= items[0]->result_type();
+  Item_result type= items[0]->result_type();
   for (i= 1 ; i < nitems ; i++)
-    type[0]= item_cmp_type(type[0], items[i]->result_type());
+    type= item_cmp_type(type, items[i]->result_type());
+  return type;
+}
+
+
+/*
+  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
+    Bitmap of collected types
+*/
+
+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++)
+    found_types|= 1<< (uint)item_cmp_type(left_result,
+                                           items[i]->result_type());
+  return found_types;
 }
 
 
@@ -1117,7 +1146,7 @@ void Item_func_between::fix_length_and_dec()
   */
   if (!args[0] || !args[1] || !args[2])
     return;
-  agg_cmp_type(thd, &cmp_type, args, 3);
+  cmp_type= agg_cmp_type(args, 3);
   if (cmp_type == STRING_RESULT &&
       agg_arg_charsets(cmp_collation, args, 3, MY_COLL_CMP_CONV, 1))
    return;
@@ -1597,94 +1626,65 @@ Item_func_nullif::is_null()
   return (null_value= (!cmp.compare() ? 1 : args[0]->null_value)); 
 }
 
+
 /*
-  CASE expression 
   Return the matching ITEM or NULL if all compares (including else) failed
+
+  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
 */
 
 Item *Item_func_case::find_item(String *str)
 {
-  String *first_expr_str, *tmp;
-  my_decimal *first_expr_dec, first_expr_dec_val;
-  longlong first_expr_int;
-  double   first_expr_real;
-  char buff[MAX_FIELD_WIDTH];
-  String buff_str(buff,sizeof(buff),default_charset());
-
-  /* These will be initialized later */
-  LINT_INIT(first_expr_str);
-  LINT_INIT(first_expr_int);
-  LINT_INIT(first_expr_real);
-  LINT_INIT(first_expr_dec);
-
-  if (first_expr_num != -1)
-  {
-    switch (cmp_type)
-    {
-      case STRING_RESULT:
-      	// We can't use 'str' here as this may be overwritten
-	if (!(first_expr_str= args[first_expr_num]->val_str(&buff_str)))
-	  return else_expr_num != -1 ? args[else_expr_num] : 0;	// Impossible
-        break;
-      case INT_RESULT:
-	first_expr_int= args[first_expr_num]->val_int();
-	if (args[first_expr_num]->null_value)
-	  return else_expr_num != -1 ? args[else_expr_num] : 0;
-	break;
-      case REAL_RESULT:
-	first_expr_real= args[first_expr_num]->val_real();
-	if (args[first_expr_num]->null_value)
-	  return else_expr_num != -1 ? args[else_expr_num] : 0;
-	break;
-      case DECIMAL_RESULT:
-        first_expr_dec= args[first_expr_num]->val_decimal(&first_expr_dec_val);
-        if (args[first_expr_num]->null_value)
-          return else_expr_num != -1 ? args[else_expr_num] : 0;
-        break;
-      case ROW_RESULT:
-      default:
-        // This case should never be chosen
-	DBUG_ASSERT(0);
-	break;
-    }
-  }
+  uint value_added_map= 0;
 
-  // Compare every WHEN argument with it and return the first match
-  for (uint i=0 ; i < ncases ; i+=2)
+  if (first_expr_num == -1)
   {
-    if (first_expr_num == -1)
+    for (uint i=0 ; i < ncases ; i+=2)
     {
       // No expression between CASE and the first WHEN
       if (args[i]->val_bool())
 	return args[i+1];
       continue;
     }
-    switch (cmp_type) {
-    case STRING_RESULT:
-      if ((tmp=args[i]->val_str(str)))		// If not null
-	if (sortcmp(tmp,first_expr_str,cmp_collation.collation)==0)
-	  return args[i+1];
-      break;
-    case INT_RESULT:
-      if (args[i]->val_int()==first_expr_int && !args[i]->null_value) 
-        return args[i+1];
-      break;
-    case REAL_RESULT: 
-      if (args[i]->val_real() == first_expr_real && !args[i]->null_value)
-        return args[i+1];
-      break;
-    case DECIMAL_RESULT:
+  }
+  else
+  {
+    /* Compare every WHEN argument with it and return the first match */
+    for (uint i=0 ; i < ncases ; i+=2)
     {
-      my_decimal value;
-      if (my_decimal_cmp(args[i]->val_decimal(&value), first_expr_dec) == 0)
-        return args[i+1];
-      break;
-    }
-    case ROW_RESULT:
-    default:
-      // This case should never be chosen
-      DBUG_ASSERT(0);
-      break;
+      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];
     }
   }
   // No, WHEN clauses all missed, return ELSE expression
@@ -1791,7 +1791,7 @@ void Item_func_case::fix_length_and_dec()
   Item **agg;
   uint nagg;
   THD *thd= current_thd;
-  
+  uint found_types= 0;
   if (!(agg= (Item**) sql_alloc(sizeof(Item*)*(ncases+1))))
     return;
   
@@ -1818,16 +1818,31 @@ void Item_func_case::fix_length_and_dec()
   */
   if (first_expr_num != -1)
   {
+    uint i;
     agg[0]= args[first_expr_num];
+    left_result_type= agg[0]->result_type();
+
     for (nagg= 0; nagg < ncases/2 ; nagg++)
       agg[nagg+1]= args[nagg*2];
     nagg++;
-    agg_cmp_type(thd, &cmp_type, agg, nagg);
-    if ((cmp_type == STRING_RESULT) &&
-        agg_arg_charsets(cmp_collation, agg, nagg, MY_COLL_CMP_CONV, 1))
-      return;
+    found_types= collect_cmp_types(agg, nagg);
+
+    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;
+      }
+    }
   }
-  
+
   if (else_expr_num == -1 || args[else_expr_num]->maybe_null)
     maybe_null=1;
   
@@ -2412,16 +2427,14 @@ static int srtcmp_in(CHARSET_INFO *cs, const String *x,const String *y)
 void Item_func_in::fix_length_and_dec()
 {
   Item **arg, **arg_end;
-  uint const_itm= 1;
+  bool const_itm= 1;
   THD *thd= current_thd;
+  uint found_types= 0;
+  uint type_cnt= 0, i;
+  left_result_type= args[0]->result_type();
+  found_types= collect_cmp_types(args, arg_count);
   
-  agg_cmp_type(thd, &cmp_type, args, arg_count);
-
-  if (cmp_type == STRING_RESULT &&
-      agg_arg_charsets(cmp_collation, args, arg_count, MY_COLL_CMP_CONV, 1))
-    return;
-
-  for (arg=args+1, arg_end=args+arg_count; arg != arg_end ; arg++)
+  for (arg= args + 1, arg_end= args + arg_count; arg != arg_end ; arg++)
   {
     if (!arg[0]->const_item())
     {
@@ -2429,26 +2442,39 @@ void Item_func_in::fix_length_and_dec()
       break;
     }
   }
-
+  for (i= 0; i <= (uint)DECIMAL_RESULT; i++)
+  {
+    if (found_types & 1 << i)
+      (type_cnt)++;
+  }
   /*
-    Row item with NULLs inside can return NULL or FALSE => 
+    Row item with NULLs inside can return NULL or FALSE =>
     they can't be processed as static
   */
-  if (const_itm && !nulls_in_row())
+  if (type_cnt == 1 && const_itm && !nulls_in_row())
   {
+    uint tmp_type;
+    Item_result cmp_type;
+    /* Only one cmp type was found. Extract it here */
+    for (tmp_type= 0; found_types - 1; found_types>>= 1)
+      tmp_type++;
+    cmp_type= (Item_result)tmp_type;
+
     switch (cmp_type) {
     case STRING_RESULT:
-      array=new in_string(arg_count-1,(qsort2_cmp) srtcmp_in, 
+      if (agg_arg_charsets(cmp_collation, args, arg_count, MY_COLL_CMP_CONV, 1))
+        return;
+      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);
+      array= new in_longlong(arg_count - 1);
       break;
     case REAL_RESULT:
-      array= new in_double(arg_count-1);
+      array= new in_double(arg_count - 1);
       break;
     case ROW_RESULT:
-      array= new in_row(arg_count-1, args[0]);
+      array= new in_row(arg_count - 1, args[0]);
       break;
     case DECIMAL_RESULT:
       array= new in_decimal(arg_count - 1);
@@ -2468,15 +2494,25 @@ void Item_func_in::fix_length_and_dec()
 	else
 	  have_null= 1;
       }
-      if ((array->used_count=j))
+      if ((array->used_count= j))
 	array->sort();
     }
   }
   else
   {
-    in_item= cmp_item::get_comparator(cmp_type, cmp_collation.collation);
-    if (cmp_type  == STRING_RESULT)
-      in_item->cmp_charset= cmp_collation.collation;
+    for (i= 0; i <= (uint) DECIMAL_RESULT; i++)
+    {
+      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_item::get_comparator((Item_result)i,
+                                     cmp_collation.collation)))
+          return;
+      }
+    }
   }
   maybe_null= args[0]->maybe_null;
   max_length= 1;
@@ -2495,25 +2531,61 @@ void Item_func_in::print(String *str)
 }
 
 
+/*
+  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
+*/
+
 longlong Item_func_in::val_int()
 {
+  cmp_item *in_item;
   DBUG_ASSERT(fixed == 1);
+  uint value_added_map= 0;
   if (array)
   {
     int tmp=array->find(args[0]);
     null_value=args[0]->null_value || (!tmp && have_null);
     return (longlong) (!null_value && tmp != negated);
   }
-  in_item->store_value(args[0]);
-  if ((null_value=args[0]->null_value))
-    return 0;
-  have_null= 0;
-  for (uint i=1 ; i < arg_count ; i++)
+
+  for (uint i= 1 ; i < arg_count ; i++)
   {
+    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;
+    }
     if (!in_item->cmp(args[i]) && !args[i]->null_value)
       return (longlong) (!negated);
     have_null|= args[i]->null_value;
   }
+
   null_value= have_null;
   return (longlong) (!null_value && negated);
 }

sql/item_cmpfunc.h

@@ -589,49 +589,6 @@ public:
 };
 
 
-class Item_func_case :public Item_func
-{
-  int first_expr_num, else_expr_num;
-  enum Item_result cached_result_type;
-  String tmp_value;
-  uint ncases;
-  Item_result cmp_type;
-  DTCollation cmp_collation;
-public:
-  Item_func_case(List<Item> &list, Item *first_expr_arg, Item *else_expr_arg)
-    :Item_func(), first_expr_num(-1), else_expr_num(-1),
-    cached_result_type(INT_RESULT)
-  {
-    ncases= list.elements;
-    if (first_expr_arg)
-    {
-      first_expr_num= list.elements;
-      list.push_back(first_expr_arg);
-    }
-    if (else_expr_arg)
-    {
-      else_expr_num= list.elements;
-      list.push_back(else_expr_arg);
-    }
-    set_arguments(list);
-  }
-  double val_real();
-  longlong val_int();
-  String *val_str(String *);
-  my_decimal *val_decimal(my_decimal *);
-  bool fix_fields(THD *thd, Item **ref);
-  void fix_length_and_dec();
-  uint decimal_precision() const;
-  table_map not_null_tables() const { return 0; }
-  enum Item_result result_type () const { return cached_result_type; }
-  const char *func_name() const { return "case"; }
-  void print(String *str);
-  Item *find_item(String *str);
-  CHARSET_INFO *compare_collation() { return cmp_collation.collation; }
-  bool check_partition_func_processor(byte *bool_arg) { return 0;}
-};
-
-
 /* Functions to handle the optimized IN */
 
 
@@ -686,6 +643,7 @@ public:
   {
     return test(compare(collation, base + pos1*size, base + pos2*size));
   }
+  virtual Item_result result_type()= 0;
 };
 
 class in_string :public in_vector
@@ -707,6 +665,7 @@ public:
     Item_string *to= (Item_string*)item;
     to->str_value= *str;
   }
+  Item_result result_type() { return STRING_RESULT; }
 };
 
 class in_longlong :public in_vector
@@ -729,6 +688,7 @@ public:
   {
     ((Item_int*)item)->value= ((longlong*)base)[pos];
   }
+  Item_result result_type() { return INT_RESULT; }
 };
 
 class in_double :public in_vector
@@ -746,6 +706,7 @@ public:
   {
     ((Item_float*)item)->value= ((double*) base)[pos];
   }
+  Item_result result_type() { return REAL_RESULT; }
 
 };
 
@@ -766,6 +727,8 @@ public:
     Item_decimal *item_dec= (Item_decimal*)item;
     item_dec->set_decimal_value(dec);
   }
+  Item_result result_type() { return DECIMAL_RESULT; }
+
 };
 
 
@@ -796,7 +759,9 @@ class cmp_item_string :public cmp_item
 protected:
   String *value_res;
 public:
+  cmp_item_string () {}
   cmp_item_string (CHARSET_INFO *cs) { cmp_charset= cs; }
+  void set_charset(CHARSET_INFO *cs) { cmp_charset= cs; }
   friend class cmp_item_sort_string;
   friend class cmp_item_sort_string_in_static;
 };
@@ -807,6 +772,8 @@ protected:
   char value_buff[STRING_BUFFER_USUAL_SIZE];
   String value;
 public:
+  cmp_item_sort_string():
+    cmp_item_string() {}
   cmp_item_sort_string(CHARSET_INFO *cs):
     cmp_item_string(cs),
     value(value_buff, sizeof(value_buff), cs) {}
@@ -828,6 +795,11 @@ public:
     return sortcmp(value_res, cmp->value_res, cmp_charset);
   } 
   cmp_item *make_same();
+  void set_charset(CHARSET_INFO *cs)
+  {
+    cmp_charset= cs;
+    value.set_quick(value_buff, sizeof(value_buff), cs);
+  }
 };
 
 class cmp_item_int :public cmp_item
@@ -908,6 +880,7 @@ public:
   ~in_row();
   void set(uint pos,Item *item);
   byte *get_value(Item *item);
+  Item_result result_type() { return ROW_RESULT; }
 };
 
 /* 
@@ -943,18 +916,109 @@ public:
   }
 };
 
+
+/*
+  The class Item_func_case is the CASE ... WHEN ... THEN ... END function
+  implementation.
+
+  When there is no expression between CASE and the first WHEN 
+  (the CASE expression) then this function simple checks all WHEN expressions
+  one after another. When some WHEN expression evaluated to TRUE then the
+  value of the corresponding THEN expression is returned.
+
+  When the CASE expression is specified then it is compared to each WHEN
+  expression individually. When an equal WHEN expression is found
+  corresponding THEN expression is returned.
+  In order to do correct comparisons several comparators are used. One for
+  each result type. Different result types that are used in particular
+  CASE ... END expression are collected in the fix_length_and_dec() member
+  function and only comparators for there result types are used.
+*/
+
+class Item_func_case :public Item_func
+{
+  int first_expr_num, else_expr_num;
+  enum Item_result cached_result_type, left_result_type;
+  String tmp_value;
+  uint ncases;
+  Item_result cmp_type;
+  DTCollation cmp_collation;
+  cmp_item *cmp_items[5]; /* For all result types */
+  cmp_item *case_item;
+public:
+  Item_func_case(List<Item> &list, Item *first_expr_arg, Item *else_expr_arg)
+    :Item_func(), first_expr_num(-1), else_expr_num(-1),
+    cached_result_type(INT_RESULT), left_result_type(INT_RESULT), case_item(0)
+  {
+    ncases= list.elements;
+    if (first_expr_arg)
+    {
+      first_expr_num= list.elements;
+      list.push_back(first_expr_arg);
+    }
+    if (else_expr_arg)
+    {
+      else_expr_num= list.elements;
+      list.push_back(else_expr_arg);
+    }
+    set_arguments(list);
+    bzero(&cmp_items, sizeof(cmp_items));
+  }
+  double val_real();
+  longlong val_int();
+  String *val_str(String *);
+  my_decimal *val_decimal(my_decimal *);
+  bool fix_fields(THD *thd, Item **ref);
+  void fix_length_and_dec();
+  uint decimal_precision() const;
+  table_map not_null_tables() const { return 0; }
+  enum Item_result result_type () const { return cached_result_type; }
+  const char *func_name() const { return "case"; }
+  void print(String *str);
+  Item *find_item(String *str);
+  CHARSET_INFO *compare_collation() { return cmp_collation.collation; }
+  bool check_partition_func_processor(byte *bool_arg) { return 0;}
+  void 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;
+  }
+};
+
+/*
+  The Item_func_in class implements the in_expr IN(values_list) function.
+
+  The current implementation distinguishes 2 cases:
+  1) all items in the value_list are constants and have the same
+    result type. This case is handled by in_vector class.
+  2) items in the value_list have different result types or there is some
+    non-constant items.
+    In this case Item_func_in employs several cmp_item objects to performs
+    comparisons of in_expr and an item from the values_list. One cmp_item
+    object for each result type. Different result types are collected in the
+    fix_length_and_dec() member function by means of collect_cmp_types()
+    function.
+*/
 class Item_func_in :public Item_func_opt_neg
 {
 public:
-  Item_result cmp_type;
   in_vector *array;
-  cmp_item *in_item;
   bool have_null;
+  Item_result left_result_type;
+  cmp_item *cmp_items[5]; /* One cmp_item for each result type */
   DTCollation cmp_collation;
 
   Item_func_in(List<Item> &list)
-    :Item_func_opt_neg(list), array(0), in_item(0), have_null(0)
+    :Item_func_opt_neg(list), array(0), have_null(0)
   {
+    bzero(&cmp_items, sizeof(cmp_items));
     allowed_arg_cols= 0;  // Fetch this value from first argument
   }
   longlong val_int();
@@ -963,12 +1027,16 @@ public:
   uint decimal_precision() const { return 1; }
   void cleanup()
   {
+    uint i;
     DBUG_ENTER("Item_func_in::cleanup");
     Item_int_func::cleanup();
     delete array;
-    delete in_item;
     array= 0;
-    in_item= 0;
+    for (i= 0; i <= (uint)DECIMAL_RESULT; i++)
+    {
+      delete cmp_items[i];
+      cmp_items[i]= 0;
+    }
     DBUG_VOID_RETURN;
   }
   optimize_type select_optimize() const

sql/opt_range.cc

@@ -4913,9 +4913,17 @@ static SEL_TREE *get_func_mm_tree(RANGE_OPT_PARAM *param, Item_func *cond_func,
   {
     Item_func_in *func=(Item_func_in*) cond_func;
 
+    /*
+      Array for IN() is constructed when all values have the same result
+      type. Tree won't be built for values with different result types,
+      so we check it here to avoid unnecessary work.
+    */
+    if (!func->array)
+      break;
+
     if (inv)
     {
-      if (func->array && func->cmp_type != ROW_RESULT)
+      if (func->array->result_type() != ROW_RESULT)
       {
         /*
           We get here for conditions in form "t.key NOT IN (c1, c2, ...)",