diff options
Diffstat (limited to 'sql/sql_select.cc')
| -rw-r--r-- | sql/sql_select.cc | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 05da4a1e750..3d618643d7e 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -15823,10 +15823,15 @@ static uint build_bitmap_for_nested_joins(List<TABLE_LIST> *join_list, /** - Set NESTED_JOIN::counter=0 in all nested joins in passed list. + Set NESTED_JOIN::counter and n_tables in all nested joins in passed list. - Recursively set NESTED_JOIN::counter=0 for all nested joins contained in - the passed join_list. + For all nested joins contained in the passed join_list (including its + children), set: + - nested_join->counter=0 + - nested_join->n_tables= {number of non-degenerate direct children}. + + Non-degenerate means non-const base table or a join nest that has a + non-degenerate child. @param join_list List of nested joins to process. It may also contain base tables which will be ignored. @@ -15849,8 +15854,11 @@ static uint reset_nj_counters(JOIN *join, List<TABLE_LIST> *join_list) if (!nested_join->n_tables) is_eliminated_nest= TRUE; } - if ((table->nested_join && !is_eliminated_nest) || - (!table->nested_join && (table->table->map & ~join->eliminated_tables))) + const table_map removed_tables= join->eliminated_tables | + join->const_table_map; + + if ((table->nested_join && !is_eliminated_nest) || + (!table->nested_join && (table->table->map & ~removed_tables))) n++; } DBUG_RETURN(n); |