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Automerge.

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This commit is contained in:
Alexey Kopytov
2009-10-30 18:59:06 +03:00
parent 2490873f3c 23b05d0002
commit b68ca5e88c
4 changed files with 100 additions and 28 deletions
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92
sql/sql_select.cc
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@ -969,6 +969,12 @@ JOIN::optimize()
DBUG_RETURN(1);
}
if (select_lex->olap == ROLLUP_TYPE && rollup_process_const_fields())
{
DBUG_PRINT("error", ("Error: rollup_process_fields() failed"));
DBUG_RETURN(1);
}
/* Remove distinct if only const tables */
select_distinct= select_distinct && (const_tables != tables);
thd_proc_info(thd, "preparing");
@ -1099,7 +1105,7 @@ JOIN::optimize()
join_tab[const_tables].select->quick->get_type() !=
QUICK_SELECT_I::QS_TYPE_GROUP_MIN_MAX))
{
if (group_list &&
if (group_list && rollup.state == ROLLUP::STATE_NONE &&
list_contains_unique_index(join_tab[const_tables].table,
find_field_in_order_list,
(void *) group_list))
@ -1143,7 +1149,8 @@ JOIN::optimize()
if (! hidden_group_fields && rollup.state == ROLLUP::STATE_NONE)
select_distinct=0;
}
else if (select_distinct && tables - const_tables == 1)
else if (select_distinct && tables - const_tables == 1 &&
rollup.state == ROLLUP::STATE_NONE)
{
/*
We are only using one table. In this case we change DISTINCT to a
@ -10212,6 +10219,7 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
for (; cur_group ; cur_group= cur_group->next, key_part_info++)
{
Field *field=(*cur_group->item)->get_tmp_table_field();
DBUG_ASSERT(field->table == table);
bool maybe_null=(*cur_group->item)->maybe_null;
key_part_info->null_bit=0;
key_part_info->field= field;
@ -15637,32 +15645,7 @@ bool JOIN::rollup_init()
{
item->maybe_null= 1;
found_in_group= 1;
if (item->const_item())
{
/*
For ROLLUP queries each constant item referenced in GROUP BY list
is wrapped up into an Item_func object yielding the same value
as the constant item. The objects of the wrapper class are never
considered as constant items and besides they inherit all
properties of the Item_result_field class.
This wrapping allows us to ensure writing constant items
into temporary tables whenever the result of the ROLLUP
operation has to be written into a temporary table, e.g. when
ROLLUP is used together with DISTINCT in the SELECT list.
Usually when creating temporary tables for a intermidiate
result we do not include fields for constant expressions.
*/
Item* new_item= new Item_func_rollup_const(item);
if (!new_item)
return 1;
new_item->fix_fields(thd, (Item **) 0);
thd->change_item_tree(it.ref(), new_item);
for (ORDER *tmp= group_tmp; tmp; tmp= tmp->next)
{
if (*tmp->item == item)
thd->change_item_tree(tmp->item, new_item);
}
}
break;
}
}
if (item->type() == Item::FUNC_ITEM && !found_in_group)
@ -15681,6 +15664,59 @@ bool JOIN::rollup_init()
}
return 0;
}
/**
Wrap all constant Items in GROUP BY list.
For ROLLUP queries each constant item referenced in GROUP BY list
is wrapped up into an Item_func object yielding the same value
as the constant item. The objects of the wrapper class are never
considered as constant items and besides they inherit all
properties of the Item_result_field class.
This wrapping allows us to ensure writing constant items
into temporary tables whenever the result of the ROLLUP
operation has to be written into a temporary table, e.g. when
ROLLUP is used together with DISTINCT in the SELECT list.
Usually when creating temporary tables for a intermidiate
result we do not include fields for constant expressions.
@retval
0 if ok
@retval
1 on error
*/
bool JOIN::rollup_process_const_fields()
{
ORDER *group_tmp;
Item *item;
List_iterator<Item> it(all_fields);
for (group_tmp= group_list; group_tmp; group_tmp= group_tmp->next)
{
if (!(*group_tmp->item)->const_item())
continue;
while ((item= it++))
{
if (*group_tmp->item == item)
{
Item* new_item= new Item_func_rollup_const(item);
if (!new_item)
return 1;
new_item->fix_fields(thd, (Item **) 0);
thd->change_item_tree(it.ref(), new_item);
for (ORDER *tmp= group_tmp; tmp; tmp= tmp->next)
{
if (*tmp->item == item)
thd->change_item_tree(tmp->item, new_item);
}
break;
}
}
it.rewind();
}
return 0;
}
/**