B4BY.588

: / proc / self / root / usr / share / mysql-test / r /
Filename : ds_mrr-big.result
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#
# Bug 12365385 STRAIGHT_JOIN QUERY QUICKLY EXHAUSTS SYSTEM+VIRT. 
#              MEMORY LEADING TO SYSTEM CRASH
#
CREATE TABLE ten (a INTEGER);
INSERT INTO ten VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
CREATE TABLE hundred (a INTEGER);
INSERT INTO hundred
SELECT a1.a + 10 * a2.a FROM ten a1, ten a2;
CREATE TABLE thousand (a INTEGER);
INSERT INTO thousand
SELECT a1.a + 10 * a2.a + 100 * a3.a FROM ten a1, ten a2, ten a3;
CREATE TABLE t1 (
pk INTEGER NOT NULL,
i1 INTEGER NOT NULL,
c1 VARCHAR(10) NOT NULL,
PRIMARY KEY (pk)
);
INSERT INTO t1
SELECT a, 1, 'MySQL' FROM thousand;
CREATE TABLE t2 (
pk INTEGER NOT NULL,
c1 VARCHAR(10) NOT NULL,
c2 varchar(10) NOT NULL,
PRIMARY KEY (pk)
);
INSERT INTO t2
SELECT a, 'MySQL', 'MySQL' FROM ten;
CREATE TABLE t3 (
pk INTEGER NOT NULL,
c1 VARCHAR(10) NOT NULL,
PRIMARY KEY (pk)
);
INSERT INTO t3
SELECT a, 'MySQL' FROM hundred;
CREATE TABLE t4 (
pk int(11) NOT NULL,
c1_key varchar(10) CHARACTER SET utf8 NOT NULL,
c2 varchar(10) NOT NULL,
c3 varchar(10) NOT NULL,
PRIMARY KEY (pk),
KEY k1 (c1_key)
);
CREATE TABLE t5 (
pk INTEGER NOT NULL,
c1 VARCHAR(10) NOT NULL,
PRIMARY KEY (pk)
);
INSERT INTO t5
SELECT a, 'MySQL' FROM ten;
set optimizer_switch=`mrr=on,mrr_cost_based=off`;
EXPLAIN SELECT STRAIGHT_JOIN *
FROM 
(t1 LEFT JOIN 
(t2 LEFT JOIN
(t3 LEFT OUTER JOIN t4 ON t3.c1 <= t4.c1_key)
ON t2.c1 = t4.c3) 
ON t1.c1 = t4.c2)
RIGHT OUTER JOIN t5 ON t2.c2 <= t5.c1
WHERE t1.i1 = 1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t5	ALL	NULL	NULL	NULL	NULL	10	NULL
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	Using where; Using join buffer (Block Nested Loop)
1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	10	Using where; Using join buffer (Block Nested Loop)
1	SIMPLE	t3	ALL	NULL	NULL	NULL	NULL	100	Using join buffer (Block Nested Loop)
1	SIMPLE	t4	ALL	k1	NULL	NULL	NULL	0	Range checked for each record (index map: 0x2)
SELECT STRAIGHT_JOIN *
FROM 
(t1 LEFT JOIN 
(t2 LEFT JOIN
(t3 LEFT OUTER JOIN t4 ON t3.c1 <= t4.c1_key)
ON t2.c1 = t4.c3) 
ON t1.c1 = t4.c2)
RIGHT OUTER JOIN t5 ON t2.c2 <= t5.c1
WHERE t1.i1 = 1;
pk	i1	c1	pk	c1	c2	pk	c1	pk	c1_key	c2	c3	pk	c1
DROP TABLE ten, hundred, thousand;
DROP TABLE t1, t2, t3, t4, t5;