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Merge

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This commit is contained in:
Sergey Petrunya
2014-10-21 00:02:24 +04:00
parent 81194d9203 1a996bde1e
commit 135bf1fcfb
3 changed files with 29 additions and 29 deletions
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28
sql/sql_select.cc
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@ -10549,6 +10549,19 @@ uint check_join_cache_usage(JOIN_TAB *tab,
cache_level--;
}
/*
Don't use BKA for materialized tables. We could actually have a
meaningful use of BKA when linked join buffers are used.
The problem is, the temp.table is not filled (actually not even opened
properly) yet, and this doesn't let us call
handler->multi_range_read_info(). It is possible to come up with
estimates, etc. without acessing the table, but it seems not to worth the
effort now.
*/
if (tab->table->pos_in_table_list->is_materialized_derived())
no_bka_cache= true;
/*
Don't use join buffering if we're dictated not to by no_jbuf_after
(This is not meaningfully used currently)
@ -10614,21 +10627,8 @@ uint check_join_cache_usage(JOIN_TAB *tab,
goto no_join_cache;
if (tab->ref.is_access_triggered())
goto no_join_cache;
/*
Don't use BKA for materialized tables. We could actually have a
meaningful use of BKA when linked join buffers are used.
The problem is, the temp.table is not filled (actually not even opened
properly) yet, and this doesn't let us call
handler->multi_range_read_info(). It is possible to come up with
estimates, etc. without acessing the table, but it seems not to worth the
effort now.
*/
if (tab->table->pos_in_table_list->is_materialized_derived())
goto no_join_cache;
if (!tab->is_ref_for_hash_join())
if (!tab->is_ref_for_hash_join() && !no_bka_cache)
{
flags= HA_MRR_NO_NULL_ENDPOINTS | HA_MRR_SINGLE_POINT;
if (tab->table->covering_keys.is_set(tab->ref.key))