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Fixed mdev-14845 Server crashes in st_join_table::is_inner_table_of_outer_join

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Do not try to apply the splitting optimization to a materialized
derived if it's specified by a select with impossible where
or if all joined tables of this select are constant.
This commit is contained in:
Igor Babaev
2018-01-02 14:09:16 -08:00
parent c664c48726
commit 86cf60a615
3 changed files with 48 additions and 14 deletions
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30
sql/opt_split.cc
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@ -291,14 +291,15 @@ struct SplM_field_ext_info: public SplM_field_info
3. this is the only select in the specification of T
4. condition pushdown is not prohibited into T
5. T is not recursive
6. T is either
6.1. a grouping table with GROUP BY list P
6. not all of this join are constant or optimized away
7. T is either
7.1. a grouping table with GROUP BY list P
or
6.2. a non-grouping table with window functions over the same non-empty
7.2. a non-grouping table with window functions over the same non-empty
partition specified by the PARTITION BY list P
7. P contains some references on the columns of the joined tables C
8. P contains some references on the columns of the joined tables C
occurred also in the select list of this join
8. There are defined some keys usable for ref access of fields from C
9. There are defined some keys usable for ref access of fields from C
with available statistics.
@retval
@ -315,15 +316,16 @@ bool JOIN::check_for_splittable_materialized()
!(derived && derived->is_materialized_derived()) || // !(2)
(unit->first_select()->next_select()) || // !(3)
(derived->prohibit_cond_pushdown) || // !(4)
(derived->is_recursive_with_table())) // !(5)
(derived->is_recursive_with_table()) || // !(5)
(table_count == 0 || const_tables == top_join_tab_count)) // !(6)
return false;
if (group_list) // (6.1)
if (group_list) // (7.1)
{
if (!select_lex->have_window_funcs())
partition_list= group_list;
}
else if (select_lex->have_window_funcs() &&
select_lex->window_specs.elements == 1) // (6.2)
select_lex->window_specs.elements == 1) // (7.2)
{
partition_list=
select_lex->window_specs.head()->partition_list->first;
@ -337,15 +339,15 @@ bool JOIN::check_for_splittable_materialized()
/*
Select from partition_list all candidates for splitting.
A candidate must be
- field item or refer to such (7.1)
- item mentioned in the select list (7.2)
- field item or refer to such (8.1)
- item mentioned in the select list (8.2)
Put info about such candidates into the array candidates
*/
table_map usable_tables= 0; // tables that contains the candidate
for (ord= partition_list; ord; ord= ord->next)
{
Item *ord_item= *ord->item;
if (ord_item->real_item()->type() != Item::FIELD_ITEM) // !(7.1)
if (ord_item->real_item()->type() != Item::FIELD_ITEM) // !(8.1)
continue;
Field *ord_field= ((Item_field *) (ord_item->real_item()))->field;
@ -359,7 +361,7 @@ bool JOIN::check_for_splittable_materialized()
uint item_no= 0;
while ((item= li++))
{
if ((*ord->item)->eq(item, 0)) // (7.2)
if ((*ord->item)->eq(item, 0)) // (8.2)
{
SplM_field_ext_info new_elem;
new_elem.producing_item= item;
@ -374,7 +376,7 @@ bool JOIN::check_for_splittable_materialized()
item_no++;
}
}
if (candidates.elements() == 0) // no candidates satisfying (7.1) && (7.2)
if (candidates.elements() == 0) // no candidates satisfying (8.1) && (8.2)
return false;
/*
@ -432,7 +434,7 @@ bool JOIN::check_for_splittable_materialized()
spl_field_cnt--;
}
if (!spl_field_cnt) // No candidate field can be accessed by ref => !(8)
if (!spl_field_cnt) // No candidate field can be accessed by ref => !(9)
return false;
/*