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| author | Igor Babaev <igor@askmonty.org> | 2017-06-07 12:45:09 -0700 |
|---|---|---|
| committer | Igor Babaev <igor@askmonty.org> | 2017-06-07 12:45:32 -0700 |
| commit | c258ca2463947fcc3d69bb50a8b5cf6906778508 (patch) | |
| tree | 67109ac2bccfda94c8b2cad15eed21e3003275fa /sql/opt_subselect.cc | |
| parent | 2cb94aa1b70fa01d9e5c1d8a7625415a0220a3d9 (diff) | |
| download | mariadb-git-c258ca2463947fcc3d69bb50a8b5cf6906778508.tar.gz | |
Fixed the bug mdev-12838.
If the optimizer chose an execution plan where
a semi-join nest were materialized and the
result of materialization was scanned to access
other tables by ref access it could build a key
over columns of the tables from the nest that
were actually inaccessible.
The patch performs a proper check whether a key
that uses columns of the tables from a materialized
semi-join nest can be employed to access outer tables.
Diffstat (limited to 'sql/opt_subselect.cc')
| -rw-r--r-- | sql/opt_subselect.cc | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/sql/opt_subselect.cc b/sql/opt_subselect.cc index d8b4de29f47..af1abb2001e 100644 --- a/sql/opt_subselect.cc +++ b/sql/opt_subselect.cc @@ -3429,6 +3429,7 @@ void fix_semijoin_strategies_for_picked_join_order(JOIN *join) table_map remaining_tables= 0; table_map handled_tabs= 0; join->sjm_lookup_tables= 0; + join->sjm_scan_tables= 0; for (tablenr= table_count - 1 ; tablenr != join->const_tables - 1; tablenr--) { POSITION *pos= join->best_positions + tablenr; @@ -3487,6 +3488,9 @@ void fix_semijoin_strategies_for_picked_join_order(JOIN *join) for (i= tablenr; i != (first + sjm->tables - 1); i--) rem_tables |= join->best_positions[i].table->table->map; + for (i= first; i < first+ sjm->tables; i++) + join->sjm_scan_tables |= join->best_positions[i].table->table->map; + POSITION dummy; join->cur_sj_inner_tables= 0; for (i= first + sjm->tables; i <= tablenr; i++) |