# # Bug #46791: Assertion failed:(table->key_read==0),function unknown # function,file sql_base.cc # CREATE TABLE t1 (a INT, b INT, KEY(a)); INSERT INTO t1 VALUES (1,1),(2,2); CREATE TABLE t2 LIKE t1; INSERT INTO t2 VALUES (1,1),(2,2); CREATE TABLE t3 LIKE t1; # should have 1 impossible where and 2 dependent subqueries EXPLAIN SELECT 1 FROM t1 WHERE NOT EXISTS (SELECT 1 FROM t2 WHERE 1 = (SELECT MIN(t2.b) FROM t3)) ORDER BY count(*); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 index NULL a 5 NULL 2 Using index; Using temporary 2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 2 Using where 3 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL no matching row in const table # should not crash the next statement SELECT 1 FROM t1 WHERE NOT EXISTS (SELECT 1 FROM t2 WHERE 1 = (SELECT MIN(t2.b) FROM t3)) ORDER BY count(*); 1 1 # should not crash: the crash is caused by the previous statement SELECT 1; 1 1 DROP TABLE t1,t2,t3; End of 5.0 tests.