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optimisation of independent ALL/ANY with aggregate function (WL#1115) (SCRUM)

Browse source 
mysql-test/r/subselect.result:
  test of new optimisation
mysql-test/t/subselect.test:
  test of new optimisation
sql/item_subselect.cc:
  special subselect to finding max/min of returned values
  optimisation of independent ALL/ANY with aggregate function
sql/item_subselect.h:
  special subselect to finding max/min of returned values
sql/sql_class.cc:
  class for collaction result for max/min subquery
sql/sql_class.h:
  class for collaction result for max/min subquery
This commit is contained in:
unknown 2003-08-12 12:38:03 +03:00
commit 964ffc34b1
6 changed files with 184 additions and 30 deletions
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84
sql/item_subselect.cc
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@ -152,8 +152,8 @@ inline table_map Item_subselect::used_tables() const
}
Item_singlerow_subselect::Item_singlerow_subselect(THD *thd,
st_select_lex *select_lex):
Item_subselect(), value(0)
st_select_lex *select_lex)
:Item_subselect(), value(0)
{
DBUG_ENTER("Item_singlerow_subselect::Item_singlerow_subselect");
init(thd, select_lex, new select_singlerow_subselect(this));
@ -163,6 +163,19 @@ Item_singlerow_subselect::Item_singlerow_subselect(THD *thd,
DBUG_VOID_RETURN;
}
Item_maxmin_subselect::Item_maxmin_subselect(THD *thd,
st_select_lex *select_lex,
bool max)
:Item_singlerow_subselect()
{
DBUG_ENTER("Item_maxmin_subselect::Item_maxmin_subselect");
init(thd, select_lex, new select_max_min_finder_subselect(this, max));
max_columns= 1;
maybe_null= 1;
max_columns= 1;
DBUG_VOID_RETURN;
}
void Item_singlerow_subselect::reset()
{
null_value= 1;
@ -499,38 +512,50 @@ Item_in_subselect::single_value_transformer(JOIN *join,
(func == &Item_bool_func2::gt_creator ||
func == &Item_bool_func2::lt_creator ||
func == &Item_bool_func2::ge_creator ||
func == &Item_bool_func2::le_creator) &&
!select_lex->group_list.elements &&
!select_lex->with_sum_func)
func == &Item_bool_func2::le_creator))
{
Item *item;
subs_type type= substype();
if (func == &Item_bool_func2::le_creator ||
func == &Item_bool_func2::lt_creator)
Item *subs;
if (!select_lex->group_list.elements &&
!select_lex->with_sum_func)
{
/*
(ALL && (> || =>)) || (ANY && (< || =<))
for ALL condition is inverted
*/
item= new Item_sum_max(*select_lex->ref_pointer_array);
Item *item;
subs_type type= substype();
if (func == &Item_bool_func2::le_creator ||
func == &Item_bool_func2::lt_creator)
{
/*
(ALL && (> || =>)) || (ANY && (< || =<))
for ALL condition is inverted
*/
item= new Item_sum_max(*select_lex->ref_pointer_array);
}
else
{
/*
(ALL && (< || =<)) || (ANY && (> || =>))
for ALL condition is inverted
*/
item= new Item_sum_min(*select_lex->ref_pointer_array);
}
*select_lex->ref_pointer_array= item;
select_lex->item_list.empty();
select_lex->item_list.push_back(item);
if (item->fix_fields(thd, join->tables_list, &item))
{
DBUG_RETURN(ERROR);
}
subs= new Item_singlerow_subselect(thd, select_lex);
}
else
{
/*
(ALL && (< || =<)) || (ANY && (> || =>))
for ALL condition is inverted
*/
item= new Item_sum_min(*select_lex->ref_pointer_array);
// remove LIMIT placed by ALL/ANY subquery
select_lex->master_unit()->global_parameters->select_limit=
HA_POS_ERROR;
subs= new Item_maxmin_subselect(thd, select_lex,
(func == &Item_bool_func2::le_creator ||
func == &Item_bool_func2::lt_creator));
}
*select_lex->ref_pointer_array= item;
select_lex->item_list.empty();
select_lex->item_list.push_back(item);
if (item->fix_fields(thd, join->tables_list, &item))
{
DBUG_RETURN(ERROR);
}
// left expression belong to outer select
SELECT_LEX *current= thd->lex.current_select, *up;
thd->lex.current_select= up= current->return_after_parsing();
@ -540,8 +565,7 @@ Item_in_subselect::single_value_transformer(JOIN *join,
DBUG_RETURN(ERROR);
}
thd->lex.current_select= current;
substitution= (*func)(left_expr,
new Item_singlerow_subselect(thd, select_lex));
substitution= (*func)(left_expr, subs);
DBUG_RETURN(OK);
}