#At lp:maria/5.2 based on revid:psergey@askmonty.org-20100225080910-38wapbgw5vpm6nax 2771 Igor Babaev 2010-03-05 Corrected Evgen's fix for bug #45191. Made sure that join buffers could be used for inner tables of any semi-join when the first match strategy is employed. modified: mysql-test/r/subselect_sj2_jcl6.result mysql-test/r/subselect_sj_jcl6.result sql/sql_join_cache.cc sql/sql_select.cc sql/sql_select.h === modified file 'mysql-test/r/subselect_sj2_jcl6.result' --- a/mysql-test/r/subselect_sj2_jcl6.result 2010-02-17 10:47:55 +0000 +++ b/mysql-test/r/subselect_sj2_jcl6.result 2010-03-05 18:54:48 +0000 @@ -713,9 +713,9 @@ c2 in (select 1 from t3, t2) and c1 in (select convert(c6,char(1)) from t2); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using where -1 PRIMARY t2 ALL NULL NULL NULL NULL 1 -1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using where -1 PRIMARY t3 ALL NULL NULL NULL NULL 2 FirstMatch(t2) +1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using join buffer +1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using where; Using join buffer +1 PRIMARY t3 ALL NULL NULL NULL NULL 2 FirstMatch(t2); Using join buffer drop table t2, t3; set join_cache_level=default; show variables like 'join_cache_level'; === modified file 'mysql-test/r/subselect_sj_jcl6.result' --- a/mysql-test/r/subselect_sj_jcl6.result 2010-02-24 11:33:42 +0000 +++ b/mysql-test/r/subselect_sj_jcl6.result 2010-03-05 18:54:48 +0000 @@ -374,8 +374,8 @@ WHERE PNUM IN (SELECT PNUM FROM PROJ)); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY STAFF ALL NULL NULL NULL NULL 5 -1 PRIMARY PROJ ALL NULL NULL NULL NULL 6 -1 PRIMARY WORKS ALL NULL NULL NULL NULL 12 Using where; FirstMatch(STAFF) +1 PRIMARY PROJ ALL NULL NULL NULL NULL 6 Using join buffer +1 PRIMARY WORKS ALL NULL NULL NULL NULL 12 Using where; FirstMatch(STAFF); Using join buffer SELECT EMPNUM, EMPNAME FROM STAFF WHERE EMPNUM IN === modified file 'sql/sql_join_cache.cc' --- a/sql/sql_join_cache.cc 2010-02-15 21:53:06 +0000 +++ b/sql/sql_join_cache.cc 2010-03-05 18:54:48 +0000 @@ -407,8 +407,10 @@ void JOIN_CACHE::set_constants() However at this moment we don't know whether we have referenced fields for the cache or not. Later when a referenced field is registered for the cache we adjust the value of the flag 'with_length'. - */ - with_length= is_key_access() || with_match_flag; + */ + with_length= is_key_access() || + join_tab->is_inner_table_of_semi_join_with_first_match() || + join_tab->is_inner_table_of_outer_join(); /* At this moment we don't know yet the value of 'referenced_fields', but in any case it can't be greater than the value of 'fields'. @@ -1304,7 +1306,7 @@ bool JOIN_CACHE::get_match_flag_by_pos(u uchar *prev_rec_ptr= prev_cache->get_rec_ref(rec_ptr); return prev_cache->get_match_flag_by_pos(prev_rec_ptr); } - DBUG_ASSERT(1); + DBUG_ASSERT(0); return FALSE; } @@ -1538,12 +1540,12 @@ bool JOIN_CACHE::read_referenced_field(C bool JOIN_CACHE::skip_record_if_match() { - DBUG_ASSERT(with_match_flag && with_length); + DBUG_ASSERT(with_length); uint offset= size_of_rec_len; if (prev_cache) offset+= prev_cache->get_size_of_rec_offset(); /* Check whether the match flag is on */ - if (test(*(pos+offset))) + if (get_match_flag_by_pos(pos+offset)) { pos+= size_of_rec_len + get_rec_length(pos); return TRUE; === modified file 'sql/sql_select.cc' --- a/sql/sql_select.cc 2010-02-17 21:59:41 +0000 +++ b/sql/sql_select.cc 2010-03-05 18:54:48 +0000 @@ -6352,10 +6352,17 @@ 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; @@ -7109,18 +7116,14 @@ uint check_join_cache_usage(JOIN_TAB *ta 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; /* === modified file 'sql/sql_select.h' --- a/sql/sql_select.h 2010-02-15 21:53:06 +0000 +++ b/sql/sql_select.h 2010-03-05 18:54:48 +0000 @@ -321,8 +321,8 @@ typedef struct st_join_table { } bool check_only_first_match() { - return last_sj_inner_tab == this || - (first_inner && first_inner->last_inner == this && + return is_inner_table_of_semi_join_with_first_match() || + (is_inner_table_of_outer_join() && table->reginfo.not_exists_optimize); } bool is_last_inner_table()