config root man

#
# 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	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	t5	NULL	ALL	NULL	NULL	NULL	NULL	10	100.00	NULL
1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	1000	10.00	Using where; Using join buffer (Block Nested Loop)
1	SIMPLE	t2	NULL	ALL	NULL	NULL	NULL	NULL	10	33.33	Using where; Using join buffer (Block Nested Loop)
1	SIMPLE	t3	NULL	ALL	NULL	NULL	NULL	NULL	100	100.00	Using join buffer (Block Nested Loop)
1	SIMPLE	t4	NULL	ALL	k1	NULL	NULL	NULL	0	0.00	Range checked for each record (index map: 0x2)
Warnings:
Note	1003	/* select#1 */ select straight_join `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`i1` AS `i1`,`test`.`t1`.`c1` AS `c1`,`test`.`t2`.`pk` AS `pk`,`test`.`t2`.`c1` AS `c1`,`test`.`t2`.`c2` AS `c2`,`test`.`t3`.`pk` AS `pk`,`test`.`t3`.`c1` AS `c1`,`test`.`t4`.`pk` AS `pk`,`test`.`t4`.`c1_key` AS `c1_key`,`test`.`t4`.`c2` AS `c2`,`test`.`t4`.`c3` AS `c3`,`test`.`t5`.`pk` AS `pk`,`test`.`t5`.`c1` AS `c1` from `test`.`t5` join `test`.`t1` join `test`.`t2` join `test`.`t3` join `test`.`t4` where ((`test`.`t4`.`c3` = `test`.`t2`.`c1`) and (`test`.`t4`.`c2` = `test`.`t1`.`c1`) and (`test`.`t1`.`i1` = 1) and (`test`.`t2`.`c2` <= `test`.`t5`.`c1`) and (convert(`test`.`t3`.`c1` using utf8) <= `test`.`t4`.`c1_key`))
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;