Hi Varun, Ok to push. On Wed, Jul 10, 2019 at 03:44:21PM +0530, Varun wrote:

revision-id: 12d294b7d39320afbf17eb5ad14f7aa651301c2c (mariadb-10.4.4-242-g12d294b7d39) parent(s): a179de04025443032745ee811a97d8da7afe8996 author: Varun Gupta committer: Varun Gupta timestamp: 2019-07-09 15:14:19 +0530 message:

Correcting the value of top_join_tab_count, to not include inner tables of semi-join nest for the tables at the top level

--- sql/opt_subselect.cc | 32 ++++++++++++++++++++++++++++++++ sql/opt_subselect.h | 1 + sql/sql_select.cc | 8 +++++--- 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/sql/opt_subselect.cc b/sql/opt_subselect.cc index f00d0ed019d..35438461bbd 100644 --- a/sql/opt_subselect.cc +++ b/sql/opt_subselect.cc @@ -3853,6 +3853,38 @@ void fix_semijoin_strategies_for_picked_join_order(JOIN *join) }

+/* + Return the number of tables at the top-level of the JOIN + + SYNOPSIS + get_number_of_tables_at_top_level() + join The join with the picked join order + + DESCRIPTION + The number of tables in the JOIN currently include all the inner tables of the + mergeable semi-joins. The function would make sure that we only count the semi-join + nest and not the inner tables of teh semi-join nest. +*/ + +uint get_number_of_tables_at_top_level(JOIN *join) +{ + uint j= 0, tables=0; + while(j < join->table_count) + { + POSITION *cur_pos= &join->best_positions[j]; + tables++; + if (cur_pos->sj_strategy == SJ_OPT_MATERIALIZE || + cur_pos->sj_strategy == SJ_OPT_MATERIALIZE_SCAN) + { + SJ_MATERIALIZATION_INFO *sjm= cur_pos->table->emb_sj_nest->sj_mat_info; + j= j + sjm->tables; + } + else + j++; + } + return tables; +} + /* Setup semi-join materialization strategy for one semi-join nest

diff --git a/sql/opt_subselect.h b/sql/opt_subselect.h index 65131f6bc89..67bfad1a539 100644 --- a/sql/opt_subselect.h +++ b/sql/opt_subselect.h @@ -320,6 +320,7 @@ void fix_semijoin_strategies_for_picked_join_order(JOIN *join);

bool setup_sj_materialization_part1(JOIN_TAB *sjm_tab); bool setup_sj_materialization_part2(JOIN_TAB *sjm_tab); +uint get_number_of_tables_at_top_level(JOIN *join);

/* diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 1f397b20b98..d5254bc1bb7 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -10153,14 +10153,16 @@ bool JOIN::get_best_combination()

if (aggr_tables > 2) aggr_tables= 2; - if (!(join_tab= (JOIN_TAB*) thd->alloc(sizeof(JOIN_TAB)* - (top_join_tab_count + aggr_tables)))) - DBUG_RETURN(TRUE);

full_join=0; hash_join= FALSE;

fix_semijoin_strategies_for_picked_join_order(this); + top_join_tab_count= get_number_of_tables_at_top_level(this); + + if (!(join_tab= (JOIN_TAB*) thd->alloc(sizeof(JOIN_TAB)* + (top_join_tab_count + aggr_tables)))) + DBUG_RETURN(TRUE);

JOIN_TAB_RANGE *root_range; if (!(root_range= new (thd->mem_root) JOIN_TAB_RANGE)) _______________________________________________ commits mailing list commits@mariadb.org https://lists.askmonty.org/cgi-bin/mailman/listinfo/commits

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