revision-id: 5a8766a98059b93798aa34d6824c6e130727d552 (mariadb-10.2.43-54-g5a8766a9805) parent(s): 53b580a91c12e9272623fc45496631be65313dd8 author: Sergei Petrunia committer: Sergei Petrunia timestamp: 2022-04-07 15:40:34 +0300 message: Better comments in Item_in_subselect::inject_in_to_exists_cond() --- sql/item_subselect.cc | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc index 92ba085af5b..e01c92b7a4f 100644 --- a/sql/item_subselect.cc +++ b/sql/item_subselect.cc @@ -2757,6 +2757,8 @@ bool Item_in_subselect::inject_in_to_exists_cond(JOIN *join_arg) } where_item= and_items(thd, join_arg->conds, where_item); + + /* This is the fix_fields() call mentioned in the comment above */ if (!where_item->fixed && where_item->fix_fields(thd, 0)) DBUG_RETURN(true); // TIMOUR TODO: call optimize_cond() for the new where clause @@ -2767,7 +2769,10 @@ bool Item_in_subselect::inject_in_to_exists_cond(JOIN *join_arg) /* Attach back the list of multiple equalities to the new top-level AND. */ if (and_args && join_arg->cond_equal) { - /* The argument list of the top-level AND may change after fix fields. */ + /* + The fix_fields() call above may have changed the argument list, so + fetch it again: + */ and_args= ((Item_cond*) join_arg->conds)->argument_list(); ((Item_cond_and *) (join_arg->conds))->m_cond_equal= *join_arg->cond_equal;