diff options
Diffstat (limited to 'sql/sql_lex.cc')
| -rw-r--r-- | sql/sql_lex.cc | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index 5e9d9a8eb17..a01b1547cf1 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -11924,9 +11924,18 @@ bool SELECT_LEX_UNIT::explainable() const false; } +/* + Determines whether the derived table was eliminated during + the call of eliminate_tables(JOIN *) made at the optimization stage + or completely optimized out (for such degenerate statements like + "SELECT 1", for example) +*/ + bool SELECT_LEX_UNIT::is_derived_eliminated() const { if (!derived) return false; + if (!derived->table) + return true; return derived->table->map & outer_select()->join->eliminated_tables; } |