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MWL#68 Subquery optimization: Efficient NOT IN execution with NULLs

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Automerge with 5.3-subqueries
This commit is contained in:
unknown
2010-03-09 12:36:15 +02:00
parent 6a138b7f01 c2924e155e
commit 292d466749
16 changed files with 374 additions and 76 deletions
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29
sql/sql_select.cc
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@ -5635,7 +5635,11 @@ void calc_used_field_length(THD *thd, JOIN_TAB *join_tab)
uint blob_length=(uint) (join_tab->table->file->stats.mean_rec_length-
(join_tab->table->s->reclength-rec_length));
rec_length+=(uint) max(4,blob_length);
}
}
/*
psergey-todo: why we don't count here rowid that we might need to store
when using DuplicateElimination?
*/
join_tab->used_fields=fields;
join_tab->used_fieldlength=rec_length;
join_tab->used_blobs=blobs;
@ -6355,10 +6359,17 @@ make_outerjoin_info(JOIN *join)
}
if (!tab->first_inner)
tab->first_inner= nested_join->first_nested;
if (tab->table->reginfo.not_exists_optimize)
tab->first_inner->table->reginfo.not_exists_optimize= 1;
if (++nested_join->counter < nested_join->n_tables)
break;
/* Table tab is the last inner table for nested join. */
nested_join->first_nested->last_inner= tab;
if (tab->first_inner->table->reginfo.not_exists_optimize)
{
for (JOIN_TAB *join_tab= tab->first_inner; join_tab <= tab; join_tab++)
join_tab->table->reginfo.not_exists_optimize= 1;
}
}
}
DBUG_VOID_RETURN;
@ -7111,19 +7122,15 @@ uint check_join_cache_usage(JOIN_TAB *tab,
*/
if (tab->use_quick == 2)
goto no_join_cache;
/*
Use join cache with FirstMatch semi-join strategy only when semi-join
contains only one table.
*/
if (tab->is_inner_table_of_semi_join_with_first_match() &&
!tab->is_single_inner_of_semi_join_with_first_match())
goto no_join_cache;
/*
Non-linked join buffers can't guarantee one match
*/
if (force_unlinked_cache &&
(tab->is_inner_table_of_outer_join() &&
!tab->is_single_inner_of_outer_join()))
if (force_unlinked_cache &&
(!tab->type == JT_ALL || cache_level <= 4) &&
((tab->is_inner_table_of_semi_join_with_first_match() &&
!tab->is_single_inner_of_semi_join_with_first_match()) ||
(tab->is_inner_table_of_outer_join() &&
!tab->is_single_inner_of_outer_join())))
goto no_join_cache;
/*