diff options
Diffstat (limited to 'sql/sql_select.cc')
| -rw-r--r-- | sql/sql_select.cc | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 720c0a22681..6e67bb11015 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -13349,10 +13349,23 @@ simplify_joins(JOIN *join, List<TABLE_LIST> *join_list, COND *conds, bool top, nested_join= table->nested_join; if (table->sj_on_expr && !in_sj) { - /* - If this is a semi-join that is not contained within another semi-join, - leave it intact (otherwise it is flattened) - */ + /* + If this is a semi-join that is not contained within another semi-join + leave it intact (otherwise it is flattened) + */ + /* + Make sure that any semi-join appear in + the join->select_lex->sj_nests list only once + */ + List_iterator_fast<TABLE_LIST> sj_it(join->select_lex->sj_nests); + TABLE_LIST *sj_nest; + while ((sj_nest= sj_it++)) + { + if (table == sj_nest) + break; + } + if (sj_nest) + continue; join->select_lex->sj_nests.push_back(table); /* |