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CREATE PROCEDURE populate_t1()
BEGIN
DECLARE i int DEFAULT 1;
START TRANSACTION;
WHILE (i <= 1000) DO
INSERT INTO t1 VALUES (i, i, CONCAT('a', i));
SET i = i + 1;
END WHILE;
COMMIT;
END|
SELECT @@innodb_fill_factor;
@@innodb_fill_factor
100
CREATE TABLE t1(
class INT,
id INT,
title VARCHAR(100)
) ENGINE=InnoDB ROW_FORMAT=COMPACT;
SELECT COUNT(*) FROM t1;
COUNT(*)
1000
/* Create index. */
CREATE INDEX idx_id ON t1(id);
CREATE INDEX idx_title ON t1(title);
/* Check table. */
CHECK TABLE t1;
Table Op Msg_type Msg_text
test.t1 check status OK
/* Select by index. */
EXPLAIN SELECT * FROM t1 WHERE id = 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref idx_id idx_id 5 const 1
EXPLAIN SELECT * FROM t1 WHERE title = 'a10';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref idx_title idx_title 403 const 1 Using index condition
SELECT * FROM t1 WHERE id = 10;
class id title
10 10 a10
SELECT * FROM t1 WHERE title = 'a10';
class id title
10 10 a10
SELECT * FROM t1 WHERE id = 500;
class id title
500 500 a500
SELECT * FROM t1 WHERE title = 'a500';
class id title
500 500 a500
SELECT * FROM t1 WHERE id = 1000;
class id title
1000 1000 a1000
SELECT * FROM t1 WHERE title = 'a1000';
class id title
1000 1000 a1000
SELECT * FROM t1 WHERE id = 1010;
class id title
SELECT * FROM t1 WHERE title = 'a1010';
class id title
DROP TABLE t1;
CREATE TABLE t1(
a INT PRIMARY KEY,
b TEXT,
c TEXT) ENGINE=InnoDB ROW_FORMAT=COMPACT;
INSERT INTO t1 VALUES
(1, REPEAT('a',10000), 'a'),
(2, REPEAT('b',20000), 'b'),
(3, REPEAT('c',40000), 'c'),
(4, REPEAT('d',60000), 'd');
ALTER TABLE t1 DROP COLUMN c;
CHECK TABLE t1;
Table Op Msg_type Msg_text
test.t1 check status OK
SELECT CHAR_LENGTH(b) FROM t1 WHERE a=4975;
CHAR_LENGTH(b)
DROP TABLE t1;
CREATE TABLE t1(
class INT,
id INT,
title VARCHAR(100)
) ENGINE=InnoDB ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=4;
SELECT COUNT(*) FROM t1;
COUNT(*)
1000
/* Create index. */
CREATE INDEX idx_id ON t1(id);
CREATE INDEX idx_title ON t1(title);
/* Check table. */
CHECK TABLE t1;
Table Op Msg_type Msg_text
test.t1 check status OK
/* Select by index. */
EXPLAIN SELECT * FROM t1 WHERE id = 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref idx_id idx_id 5 const 1
EXPLAIN SELECT * FROM t1 WHERE title = 'a10';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref idx_title idx_title 403 const 1 Using index condition
SELECT * FROM t1 WHERE id = 10;
class id title
10 10 a10
SELECT * FROM t1 WHERE title = 'a10';
class id title
10 10 a10
SELECT * FROM t1 WHERE id = 500;
class id title
500 500 a500
SELECT * FROM t1 WHERE title = 'a500';
class id title
500 500 a500
SELECT * FROM t1 WHERE id = 1000;
class id title
1000 1000 a1000
SELECT * FROM t1 WHERE title = 'a1000';
class id title
1000 1000 a1000
SELECT * FROM t1 WHERE id = 1010;
class id title
SELECT * FROM t1 WHERE title = 'a1010';
class id title
DROP TABLE t1;
CREATE TABLE t1(
a INT PRIMARY KEY,
b TEXT,
c TEXT) ENGINE=InnoDB ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=4;
INSERT INTO t1 VALUES
(1, REPEAT('a',10000), 'a'),
(2, REPEAT('b',20000), 'b'),
(3, REPEAT('c',40000), 'c'),
(4, REPEAT('d',60000), 'd');
ALTER TABLE t1 DROP COLUMN c;
CHECK TABLE t1;
Table Op Msg_type Msg_text
test.t1 check status OK
SELECT CHAR_LENGTH(b) FROM t1 WHERE a=4975;
CHAR_LENGTH(b)
DROP TABLE t1;
DROP PROCEDURE populate_t1;
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