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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 where; Using index; Using temporary
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 2 Using where
3 DEPENDENT SUBQUERY t3 system NULL NULL NULL NULL 0 const row not found
# 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.
#
# BUG#46743 "Azalea processing correlated, aggregate SELECT
# subqueries incorrectly"
#
CREATE TABLE t1 (c int);
INSERT INTO t1 VALUES (NULL);
CREATE TABLE t2 (d int , KEY (d));
INSERT INTO t2 VALUES (NULL),(NULL);
0 rows in subquery
SELECT 1 AS RESULT FROM t2,t1 WHERE d = c;
RESULT
base query
SELECT (SELECT 1 FROM t2 WHERE d = c) AS RESULT FROM t1 ;
RESULT
NULL
EXPLAIN EXTENDED SELECT (SELECT 1 FROM t2 WHERE d = c) AS RESULT FROM t1 ;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
Warnings:
Note 1276 Field or reference 'test.t1.c' of SELECT #2 was resolved in SELECT #1
Note 1003 select <expr_cache><NULL>((select 1 from `test`.`t2` where 0)) AS `RESULT` from `test`.`t1`
first equivalent variant
SELECT (SELECT 1 FROM t2 WHERE d = IFNULL(c,NULL)) AS RESULT FROM t1 GROUP BY c ;
RESULT
NULL
EXPLAIN EXTENDED SELECT (SELECT 1 FROM t2 WHERE d = IFNULL(c,NULL)) AS RESULT FROM t1 GROUP BY c;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
Warnings:
Note 1276 Field or reference 'test.t1.c' of SELECT #2 was resolved in SELECT #1
Note 1003 select <expr_cache><NULL>((select 1 from `test`.`t2` where 0)) AS `RESULT` from `test`.`t1` group by NULL
second equivalent variant
SELECT (SELECT 1 FROM t2 WHERE d = c) AS RESULT FROM t1 GROUP BY c ;
RESULT
NULL
EXPLAIN EXTENDED SELECT (SELECT 1 FROM t2 WHERE d = c) AS RESULT FROM t1 GROUP BY c ;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
Warnings:
Note 1276 Field or reference 'test.t1.c' of SELECT #2 was resolved in SELECT #1
Note 1003 select <expr_cache><NULL>((select 1 from `test`.`t2` where 0)) AS `RESULT` from `test`.`t1` group by NULL
DROP TABLE t1,t2;
#
# BUG#45928 "Differing query results depending on MRR and
# engine_condition_pushdown settings"
#
CREATE TABLE `t1` (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`time_nokey` time NOT NULL,
`varchar_key` varchar(1) NOT NULL,
`varchar_nokey` varchar(1) NOT NULL,
PRIMARY KEY (`pk`),
KEY `varchar_key` (`varchar_key`)
) AUTO_INCREMENT=12 DEFAULT CHARSET=latin1;
INSERT INTO `t1` VALUES (10,'00:00:00','i','i'),(11,'00:00:00','','');
set @old_optimizer_switch = @@session.optimizer_switch,
@old_optimizer_use_mrr = @@session.optimizer_use_mrr,
@old_engine_condition_pushdown = @@session.engine_condition_pushdown;
SET SESSION OPTIMIZER_SWITCH = 'materialization=off,semijoin=off,loosescan=off,firstmatch=off';
SET SESSION optimizer_use_mrr = 'force';
SET SESSION engine_condition_pushdown = 1;
SELECT `time_nokey` G1 FROM t1 WHERE ( `varchar_nokey` , `varchar_key` ) IN (
SELECT `varchar_nokey` , `varchar_nokey` ) AND `varchar_key` >= 'c' HAVING G1 ORDER
BY `pk` ;
G1
set @@session.optimizer_switch = @old_optimizer_switch,
@@session.optimizer_use_mrr = @old_optimizer_use_mrr,
@@session.engine_condition_pushdown = @old_engine_condition_pushdown;
DROP TABLE t1;
#
# BUG#45863 "Assertion failed: (fixed == 0), function fix_fields(),
# file item.cc, line 4448"
#
DROP TABLE IF EXISTS C, BB;
CREATE TABLE C (
varchar_nokey varchar(1) NOT NULL
);
INSERT INTO C VALUES
('k'),('a'),(''),('u'),('e'),('v'),('i'),
('t'),('u'),('f'),('u'),('m'),('j'),('f'),
('v'),('j'),('g'),('e'),('h'),('z');
CREATE TABLE BB (
varchar_nokey varchar(1) NOT NULL
);
INSERT INTO BB VALUES ('i'),('t');
SELECT varchar_nokey FROM C
WHERE (varchar_nokey, OUTR) IN (SELECT varchar_nokey
FROM BB);
ERROR 21000: Operand should contain 2 column(s)
SELECT varchar_nokey FROM C
WHERE (varchar_nokey, OUTR) IN (SELECT varchar_nokey, varchar_nokey
FROM BB);
ERROR 42S22: Unknown column 'OUTR' in 'IN/ALL/ANY subquery'
DROP TABLE C,BB;
#
# During work with BUG#45863 I had problems with a query that was
# optimized differently in regular and prepared mode.
# Because there was a bug in one of the selected strategies, I became
# aware of the problem. Adding an EXPLAIN query to catch this.
DROP TABLE IF EXISTS t1, t2, t3;
CREATE TABLE t1
(EMPNUM CHAR(3) NOT NULL,
EMPNAME CHAR(20),
GRADE DECIMAL(4),
CITY CHAR(15));
CREATE TABLE t2
(PNUM CHAR(3) NOT NULL,
PNAME CHAR(20),
PTYPE CHAR(6),
BUDGET DECIMAL(9),
CITY CHAR(15));
CREATE TABLE t3
(EMPNUM CHAR(3) NOT NULL,
PNUM CHAR(3) NOT NULL,
HOURS DECIMAL(5));
INSERT INTO t1 VALUES ('E1','Alice',12,'Deale');
INSERT INTO t1 VALUES ('E2','Betty',10,'Vienna');
INSERT INTO t1 VALUES ('E3','Carmen',13,'Vienna');
INSERT INTO t1 VALUES ('E4','Don',12,'Deale');
INSERT INTO t1 VALUES ('E5','Ed',13,'Akron');
INSERT INTO t2 VALUES ('P1','MXSS','Design',10000,'Deale');
INSERT INTO t2 VALUES ('P2','CALM','Code',30000,'Vienna');
INSERT INTO t2 VALUES ('P3','SDP','Test',30000,'Tampa');
INSERT INTO t2 VALUES ('P4','SDP','Design',20000,'Deale');
INSERT INTO t2 VALUES ('P5','IRM','Test',10000,'Vienna');
INSERT INTO t2 VALUES ('P6','PAYR','Design',50000,'Deale');
INSERT INTO t3 VALUES ('E1','P1',40);
INSERT INTO t3 VALUES ('E1','P2',20);
INSERT INTO t3 VALUES ('E1','P3',80);
INSERT INTO t3 VALUES ('E1','P4',20);
INSERT INTO t3 VALUES ('E1','P5',12);
INSERT INTO t3 VALUES ('E1','P6',12);
INSERT INTO t3 VALUES ('E2','P1',40);
INSERT INTO t3 VALUES ('E2','P2',80);
INSERT INTO t3 VALUES ('E3','P2',20);
INSERT INTO t3 VALUES ('E4','P2',20);
INSERT INTO t3 VALUES ('E4','P4',40);
INSERT INTO t3 VALUES ('E4','P5',80);
SET @old_optimizer_switch = @@session.optimizer_switch;
SET @old_join_cache_level = @@session.join_cache_level;
SET SESSION optimizer_switch = 'firstmatch=on,loosescan=on,materialization=on,semijoin=on';
SET SESSION join_cache_level = 1;
CREATE UNIQUE INDEX t1_IDX ON t1(EMPNUM);
EXPLAIN SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'));
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL t1_IDX NULL NULL NULL 5
1 PRIMARY subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'))";
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL t1_IDX NULL NULL NULL 5
1 PRIMARY subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL t1_IDX NULL NULL NULL 5
1 SIMPLE subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
DEALLOCATE PREPARE stmt;
DROP INDEX t1_IDX ON t1;
CREATE INDEX t1_IDX ON t1(EMPNUM);
EXPLAIN SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'));
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL t1_IDX NULL NULL NULL 5
1 PRIMARY subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'))";
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL t1_IDX NULL NULL NULL 5
1 PRIMARY subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL t1_IDX NULL NULL NULL 5
1 SIMPLE subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
DEALLOCATE PREPARE stmt;
DROP INDEX t1_IDX ON t1;
EXPLAIN SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'));
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 5
1 PRIMARY subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'))";
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 5
1 PRIMARY subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 5
1 SIMPLE subselect2 eq_ref unique_key unique_key 3 func 1
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 Using where
2 SUBQUERY t3 ALL NULL NULL NULL NULL 12 Using where; Using join buffer
DEALLOCATE PREPARE stmt;
SET SESSION optimizer_switch = @old_optimizer_switch;
SET SESSION join_cache_level = @old_join_cache_level;
DROP TABLE t1, t2, t3;
#
# BUG#45221 Query SELECT pk FROM C WHERE pk IN (SELECT int_key) failing
#
CREATE TABLE t1 (
i1_key INT,
i2 INT,
i3 INT,
KEY i1_index (i1_key)
);
INSERT INTO t1 VALUES (9,1,2), (9,2,1);
CREATE TABLE t2 (
pk INT NOT NULL,
i1 INT,
PRIMARY KEY (pk)
);
INSERT INTO t2 VALUES (9,1);
# Enable Index condition pushdown
SELECT @old_icp:=@@engine_condition_pushdown;
@old_icp:=@@engine_condition_pushdown
#
SET SESSION engine_condition_pushdown = 'ON';
SELECT pk
FROM t2
WHERE
pk IN (
SELECT i1_key
FROM t1
WHERE t1.i2 < t1.i3 XOR t2.i1 > 1
ORDER BY t1.i2 desc);
pk
9
# Restore old value for Index condition pushdown
SET SESSION engine_condition_pushdown=@old_icp;
DROP TABLE t1,t2;
|
