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#
# 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;
#
# Bug #47106: Crash / segfault on adding EXPLAIN to a non-crashing
# query
#
CREATE TABLE t1 (
a INT,
b INT,
PRIMARY KEY (a),
KEY b (b)
);
INSERT INTO t1 VALUES (1, 1), (2, 1);
CREATE TABLE t2 LIKE t1;
INSERT INTO t2 SELECT * FROM t1;
CREATE TABLE t3 LIKE t1;
INSERT INTO t3 SELECT * FROM t1;
# Should not crash.
# Should have 1 impossible where and 2 dependent subqs.
EXPLAIN
SELECT
(SELECT 1 FROM t1,t2 WHERE t2.b > t3.b)
FROM t3 WHERE 1 = 0 GROUP BY 1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
2 DEPENDENT SUBQUERY t1 index NULL PRIMARY 4 NULL 2 Using index
2 DEPENDENT SUBQUERY t2 index b b 5 NULL 2 Using where; Using index; Using join buffer
# should return 0 rows
SELECT
(SELECT 1 FROM t1,t2 WHERE t2.b > t3.b)
FROM t3 WHERE 1 = 0 GROUP BY 1;
(SELECT 1 FROM t1,t2 WHERE t2.b > t3.b)
DROP TABLE t1,t2,t3;
End of 5.0 tests.
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