diff options
Diffstat (limited to 'sql/opt_subselect.cc')
| -rw-r--r-- | sql/opt_subselect.cc | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/sql/opt_subselect.cc b/sql/opt_subselect.cc index 8378c3feb89..4c7925e3e71 100644 --- a/sql/opt_subselect.cc +++ b/sql/opt_subselect.cc @@ -830,12 +830,14 @@ bool subquery_types_allow_materialization(Item_in_subselect *in_subs) in_subs->sjm_scan_allowed= FALSE; bool all_are_fields= TRUE; + uint32 total_key_length = 0; for (uint i= 0; i < elements; i++) { Item *outer= in_subs->left_expr->element_index(i); Item *inner= it++; all_are_fields &= (outer->real_item()->type() == Item::FIELD_ITEM && inner->real_item()->type() == Item::FIELD_ITEM); + total_key_length += inner->max_length; if (outer->cmp_type() != inner->cmp_type()) DBUG_RETURN(FALSE); switch (outer->cmp_type()) { @@ -866,6 +868,14 @@ bool subquery_types_allow_materialization(Item_in_subselect *in_subs) } } + /* + Make sure that create_tmp_table will not fail due to too long keys. + See MDEV-7122. This check is performed inside create_tmp_table also and + we must do it so that we know the table has keys created. + */ + if (total_key_length > HA_MAX_KEY_LENGTH || elements > HA_MAX_KEY_SEG) + DBUG_RETURN(FALSE); + in_subs->types_allow_materialization= TRUE; in_subs->sjm_scan_allowed= all_are_fields; DBUG_PRINT("info",("subquery_types_allow_materialization: ok, allowed")); |