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|
#
# WL#6266 Make use of hidden key parts
#
#
# Optimizer switch use_index_extensions=off
#
set optimizer_switch= "use_index_extensions=off";
CREATE TABLE t1
(
pk_1 INT,
pk_2 INT,
f1 DATETIME,
f2 INT,
PRIMARY KEY(pk_1, pk_2),
KEY k1(f1),
KEY k2(f2)
) ENGINE = InnoDB;
INSERT INTO t1 VALUES
(1, 1, '2000-01-01', 1), (1, 2, '2000-01-02', 2), (1, 3, '2000-01-03', 3), (1, 4, '2000-01-04', 4), (1, 5, '2000-01-05', 5),
(2, 1, '2000-01-01', 6), (2, 2, '2000-01-02', 7), (2, 3, '2000-01-03', 8), (2, 4, '2000-01-04', 9), (2, 5, '2000-01-05', 10),
(3, 1, '2000-01-01', 11), (3, 2, '2000-01-02', 12), (3, 3, '2000-01-03', 13), (3, 4, '2000-01-04', 14), (3, 5, '2000-01-05', 15),
(4, 1, '2000-01-01', 16), (4, 2, '2000-01-02', 17), (4, 3, '2000-01-03', 18), (4, 4, '2000-01-04', 19), (4, 5, '2000-01-05', 20),
(5, 1, '2000-01-01', 21), (5, 2, '2000-01-02', 22), (5, 3, '2000-01-03', 23), (5, 4, '2000-01-04', 24), (5, 5, '2000-01-05', 25),
(6, 1, '2000-01-06', 26), (6, 2, '2000-01-06', 27), (6, 3, '2000-01-03', 28), (6, 4, '2000-01-06', 29), (6, 5, '2000-01-06', 30),
(7, 1, '2000-01-06', 31), (7, 2, '2000-01-06', 32), (7, 3, '2000-01-03', 33), (7, 4, '2000-01-06', 34), (7, 5, '2000-01-06', 35),
(8, 1, '2000-01-06', 36), (8, 2, '2000-01-06', 37), (8, 3, '2000-01-03', 38), (8, 4, '2000-01-06', 39), (8, 5, '2000-01-06', 40),
(9, 1, '2000-01-06', 41), (9, 2, '2000-01-06', 42), (9, 3, '2000-01-03', 43), (9, 4, '2000-01-06', 44), (9, 5, '2000-01-06', 45);
INSERT INTO t1 VALUES
(11, 1, '2000-01-01', 1), (11, 2, '2000-01-02', 2), (11, 3, '2000-01-03', 3), (11, 4, '2000-01-04', 4), (11, 5, '2000-01-05', 5),
(12, 1, '2000-01-01', 6), (12, 2, '2000-01-02', 7), (12, 3, '2000-01-03', 8), (12, 4, '2000-01-04', 9), (12, 5, '2000-01-05', 10),
(13, 1, '2000-01-01', 11), (13, 2, '2000-01-02', 12), (13, 3, '2000-01-03', 13), (13, 4, '2000-01-04', 14), (13, 5, '2000-01-05', 15),
(14, 1, '2000-01-01', 16), (14, 2, '2000-01-02', 17), (14, 3, '2000-01-03', 18), (14, 4, '2000-01-04', 19), (14, 5, '2000-01-05', 20),
(15, 1, '2000-01-01', 1), (15, 2, '2000-01-02', 2), (15, 3, '2000-01-03', 3), (15, 4, '2000-01-04', 4), (15, 5, '2000-01-05', 5),
(16, 1, '2000-01-06', 6), (16, 2, '2000-01-06', 7), (16, 3, '2000-01-03', 8), (16, 4, '2000-01-06', 9), (16, 5, '2000-01-06', 10),
(17, 1, '2000-01-06', 31), (17, 2, '2000-01-06', 32), (17, 3, '2000-01-03', 33), (17, 4, '2000-01-06', 34), (17, 5, '2000-01-06', 35),
(18, 1, '2000-01-06', 36), (18, 2, '2000-01-06', 37), (18, 3, '2000-01-03', 38), (18, 4, '2000-01-06', 39), (18, 5, '2000-01-06', 40),
(19, 1, '2000-01-06', 1), (19, 2, '2000-01-06', 2), (19, 3, '2000-01-03', 3), (19, 4, '2000-01-06', 4), (19, 5, '2000-01-06', 5);
INSERT INTO t1 VALUES
(21, 1, '2000-01-01', 1), (21, 2, '2000-01-02', 2), (31, 3, '2000-01-03', 3), (41, 4, '2000-01-04', 4), (51, 5, '2000-01-05', 5),
(22, 1, '2000-01-01', 6), (22, 2, '2000-01-02', 7), (32, 3, '2000-01-03', 8), (42, 4, '2000-01-04', 9), (52, 5, '2000-01-05', 10),
(23, 1, '2000-01-01', 11), (23, 2, '2000-01-02', 12), (33, 3, '2000-01-03', 13), (43, 4, '2000-01-04', 14), (53, 5, '2000-01-05', 15),
(24, 1, '2000-01-01', 16), (24, 2, '2000-01-02', 17), (34, 3, '2000-01-03', 18), (44, 4, '2000-01-04', 19), (54, 5, '2000-01-05', 20),
(25, 1, '2000-01-01', 1), (25, 2, '2000-01-02', 2), (35, 3, '2000-01-03', 3), (45, 4, '2000-01-04', 4), (55, 5, '2000-01-05', 5),
(26, 1, '2000-01-06', 6), (26, 2, '2000-01-06', 7), (36, 3, '2000-01-03', 8), (46, 4, '2000-01-06', 9), (56, 5, '2000-01-06', 10),
(27, 1, '2000-01-06', 31), (27, 2, '2000-01-06', 32), (37, 3, '2000-01-03', 33), (47, 4, '2000-01-06', 34), (57, 5, '2000-01-06', 35),
(28, 1, '2000-01-06', 36), (28, 2, '2000-01-06', 37), (38, 3, '2000-01-03', 38), (48, 4, '2000-01-06', 39), (58, 5, '2000-01-06', 40),
(29, 1, '2000-01-06', 1), (29, 2, '2000-01-06', 2), (39, 3, '2000-01-03', 3), (49, 4, '2000-01-06', 4), (59, 5, '2000-01-06', 5);
INSERT INTO t1 SELECT pk_1 + 60, pk_2, f1, f2 FROM t1;
INSERT INTO t1 SELECT pk_1 + 120, pk_2, f1, f2 FROM t1;
INSERT INTO t1 SELECT pk_1 + 240, pk_2, f1, f2 FROM t1;
INSERT INTO t1 SELECT pk_1, pk_2 + 10, f1, f2 FROM t1;
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
#
# REF access optimization
#
EXPLAIN SELECT count(*) FROM t1 WHERE pk_1 = 3 and f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref PRIMARY,k1 PRIMARY 4 const # Using where
FLUSH STATUS;
SELECT count(*) FROM t1 WHERE pk_1 = 3 and f1 = '2000-01-03';
count(*)
2
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 10
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
EXPLAIN SELECT pk_2 FROM t1 WHERE pk_1 = 3 and f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref PRIMARY,k1 PRIMARY 4 const # Using where
FLUSH STATUS;
SELECT pk_2 FROM t1 WHERE pk_1 = 3 and f1 = '2000-01-03';
pk_2
3
13
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 10
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
#
# RANGE access optimization
#
EXPLAIN SELECT count(*) FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,k1 PRIMARY 4 NULL # Using where
FLUSH STATUS;
SELECT count(*) FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03';
count(*)
6
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 30
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
EXPLAIN SELECT pk_1, pk_2 FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,k1 PRIMARY 4 NULL # Using where
FLUSH STATUS;
SELECT pk_1, pk_2 FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03';
pk_1 pk_2
3 3
3 13
4 3
4 13
5 3
5 13
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 30
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
#
# MAX/MIN optimization
#
EXPLAIN SELECT MIN(pk_1) FROM t1 WHERE f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref k1 k1 6 const # Using index
FLUSH STATUS;
SELECT MIN(pk_1) FROM t1 WHERE f1 = '2000-01-03';
MIN(pk_1)
1
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 432
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
EXPLAIN SELECT MIN(pk_1) FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,k1 PRIMARY 4 NULL # Using where
FLUSH STATUS;
SELECT MIN(pk_1) FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03';
MIN(pk_1)
3
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 30
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
EXPLAIN SELECT MAX(pk_1) FROM t1 WHERE f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref k1 k1 6 const # Using index
FLUSH STATUS;
SELECT MAX(pk_1) FROM t1 WHERE f1 = '2000-01-03';
MAX(pk_1)
459
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 432
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
EXPLAIN SELECT MAX(pk_1) FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,k1 PRIMARY 4 NULL # Using where
FLUSH STATUS;
SELECT MAX(pk_1) FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03';
MAX(pk_1)
5
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 30
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
#
# Loose index scan
#
EXPLAIN SELECT MIN(pk_1) FROM t1 WHERE f2 BETWEEN 13 AND 14 GROUP BY f2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range k2 k2 5 NULL # Using where; Using index
FLUSH STATUS;
SELECT MIN(pk_1) FROM t1 WHERE f2 BETWEEN 13 AND 14 GROUP BY f2;
MIN(pk_1)
3
3
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 96
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
EXPLAIN SELECT MIN(pk_1) FROM t1 WHERE f2 IN (1, 2) GROUP BY f2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range k2 k2 5 NULL # Using where; Using index
FLUSH STATUS;
SELECT MIN(pk_1) FROM t1 WHERE f2 IN (1, 2) GROUP BY f2;
MIN(pk_1)
1
1
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 2
Handler_read_last 0
Handler_read_next 224
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
#
# JOIN optimization
#
EXPLAIN SELECT count(*) FROM t1 AS t1 JOIN t1 AS t2
ON t2.pk_1 = t1.pk_1 WHERE t1.f1 = '2000-01-03' AND t2.f1 = '2000-01-03';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref PRIMARY,k1 k1 6 const # Using index
1 SIMPLE t2 ref PRIMARY,k1 k1 6 const # Using where; Using index
FLUSH STATUS;
SELECT count(*) FROM t1 AS t1 JOIN t1 AS t2
ON t2.pk_1 = t1.pk_1 WHERE t1.f1 = '2000-01-03' AND t2.f1 = '2000-01-03';
count(*)
864
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 433
Handler_read_last 0
Handler_read_next 187056
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
#
# Optimization of sorting
#
EXPLAIN SELECT f1, pk_1, pk_2 FROM t1 WHERE pk_1 = 3 AND f1 = '2000-01-03'
ORDER BY pk_2 DESC LIMIT 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref PRIMARY,k1 PRIMARY 4 const # Using where
FLUSH STATUS;
SELECT f1, pk_1, pk_2 FROM t1 WHERE pk_1 = 3 AND f1 = '2000-01-03'
ORDER BY pk_2 DESC LIMIT 5;
f1 pk_1 pk_2
2000-01-03 00:00:00 3 13
2000-01-03 00:00:00 3 3
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 0
Handler_read_prev 10
Handler_read_rnd 0
Handler_read_rnd_next 0
EXPLAIN SELECT f1, pk_1, pk_2 FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03'
ORDER BY pk_2 DESC LIMIT 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,k1 PRIMARY 4 NULL # Using where; Using filesort
FLUSH STATUS;
SELECT f1, pk_1, pk_2 FROM t1 WHERE pk_1 BETWEEN 3 AND 5 AND f1 = '2000-01-03'
ORDER BY pk_2 DESC LIMIT 5;
f1 pk_1 pk_2
2000-01-03 00:00:00 3 13
2000-01-03 00:00:00 4 13
2000-01-03 00:00:00 5 13
2000-01-03 00:00:00 3 3
2000-01-03 00:00:00 4 3
SHOW STATUS LIKE 'handler_read%';
Variable_name Value
Handler_read_first 0
Handler_read_key 1
Handler_read_last 0
Handler_read_next 30
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 0
DROP TABLE t1;
#
# Max key part limitation
#
CREATE TABLE t1
(
f1 INT, f2 INT, f3 INT, f4 INT, f5 INT, f6 INT, f7 INT, f8 INT, f9 INT, f10 INT,
f11 INT, f12 INT, f13 INT, f14 INT, f15 INT, f16 INT, f17 INT, f18 INT,
PRIMARY KEY (f1, f2, f3, f4, f5, f6, f7, f8, f9, f10),
KEY k1 (f11, f12, f13, f14, f15, f16, f17)
) ENGINE = InnoDB;
EXPLAIN SELECT f17 FROM t1 FORCE INDEX (k1) WHERE
f1 = 0 AND f2 = 0 AND f3 = 0 AND f4 = 0 AND f5 = 0 AND
f6 = 0 AND f7 = 0 AND f8 = 0 AND f9 = 0 AND f10 = 0 AND
f11 = 0 AND f12 = 0 AND f13 = 0 AND f14 = 0 AND
f15 = 0 AND f16 = 0 AND f17 = 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref k1 k1 35 const,const,const,const,const,const,const # Using where; Using index
EXPLAIN SELECT f17 FROM t1 FORCE INDEX (k1) WHERE
f1 = 0 AND f2 = 0 AND f3 = 0 AND f4 = 0 AND f5 = 0 AND
f6 = 0 AND f7 = 0 AND f8 = 0 AND f9 = 0 AND
f11 = 0 AND f12 = 0 AND f13 = 0 AND f14 = 0 AND
f15 = 0 AND f16 = 0 AND f17 = 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref k1 k1 35 const,const,const,const,const,const,const # Using where; Using index
DROP TABLE t1;
#
# Max key length limitation
#
CREATE TABLE t1
(
f1 VARCHAR(500), f2 VARCHAR(500), f3 VARCHAR(500),
f4 VARCHAR(500), f5 VARCHAR(500), f6 VARCHAR(500),
f7 VARCHAR(500),
PRIMARY KEY (f1, f2, f3, f4),
KEY k1 (f5, f6, f7)
) ENGINE = InnoDB;
EXPLAIN SELECT f5 FROM t1 FORCE INDEX (k1) WHERE
f1 = 'a' AND f2 = 'a' AND f3 = 'a' AND f4 = 'a' AND
f5 = 'a' AND f6 = 'a' AND f7 = 'a';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref k1 k1 1509 const,const,const # Using where; Using index
EXPLAIN SELECT f5 FROM t1 FORCE INDEX (k1) WHERE
f1 = 'a' AND f2 = 'a' AND f3 = 'a' AND
f5 = 'a' AND f6 = 'a' AND f7 = 'a';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref k1 k1 1509 const,const,const # Using where; Using index
EXPLAIN SELECT f5 FROM t1 FORCE INDEX (k1) WHERE
f1 = 'a' AND f2 = 'a' AND f4 = 'a' AND
f5 = 'a' AND f6 = 'a' AND f7 = 'a';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref k1 k1 1509 const,const,const # Using where; Using index
DROP TABLE t1;
#
# Unique extended key
#
CREATE TABLE t1
(
pk INT NOT NULL auto_increment,
f1 INT NOT NULL,
KEY (f1),
PRIMARY KEY (pk)
) ENGINE = INNODB;
CREATE TABLE t2
(
f1 INT,
f2 INT
) ENGINE = INNODB;
INSERT INTO t1(f1) VALUES (1),(2);
INSERT INTO t1(f1) SELECT f1 + 2 FROM t1;
INSERT INTO t1(f1) SELECT f1 + 4 FROM t1;
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
INSERT INTO t2 VALUES (1,1), (2,2);
EXPLAIN SELECT t2.f1 FROM t2 JOIN t1 IGNORE INDEX(primary) ON t2.f1 = t1.pk and t2.f2 = t1.f1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where
1 SIMPLE t1 ref f1 f1 4 test.t2.f2 1 Using where; Using index
FLUSH STATUS;
SELECT t2.f1 FROM t2 JOIN t1 IGNORE INDEX(primary) ON t2.f1 = t1.pk and t2.f2 = t1.f1;
f1
1
2
SHOW STATUS LIKE 'Handler_read%';
Variable_name Value
Handler_read_first 1
Handler_read_key 3
Handler_read_last 0
Handler_read_next 2
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 3
DROP TABLE t1, t2;
set optimizer_switch=default;
|
