MySQL分区表验证

• MySQL分区表
• 快速验证
• 创建分区表
• SQL验证

MySQL分区表

针对MySQL 5.6版本以后引入的分区表做些简单验证。

快速验证

创建分区表

'CREATE TABLE `tb_raw_order` (
`order_id` int(11) NOT NULL AUTO_INCREMENT,
`buyer_id` varchar(10) COLLATE utf8mb4_unicode_ci DEFAULT NULL,
`total_amount` decimal(65,4) DEFAULT NULL,
PRIMARY KEY (`order_id`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci
PARTITION BY HASH (order_id)
PARTITIONS 4;

DROP TABLE IF EXISTS `tb_raw_order_np`;
CREATE TABLE `tb_raw_order_np` (
`order_id` int(11) NOT NULL AUTO_INCREMENT,
`buyer_id` varchar(10) COLLATE utf8mb4_unicode_ci DEFAULT NULL,
`total_amount` decimal(65,4) DEFAULT NULL,
PRIMARY KEY (`order_id`)
) ENGINE=InnoDB AUTO_INCREMENT=800001 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

show create table tb_raw_order;
show table status ;

SQL验证

1. 插入数据

INSERT INTO tb_raw_order(buyer_id, total_amount) VALUES('allen', 100.00), ('jack', 2.3434), ('john', 9.99), ('john', 10);

1. 查询分区数

select
partition_name part,
partition_expression expr,
partition_description descr,
table_rows
from information_schema.partitions  where
table_schema = schema()
and table_name='tb_raw_order';

1. 查询分区数据

SELECT * FROM testdb2.tb_raw_order ;
SELECT * FROM testdb2.tb_raw_order partition(p0);
SELECT * FROM testdb2.tb_raw_order partition(p1);
SELECT * FROM testdb2.tb_raw_order partition(p2);
SELECT * FROM testdb2.tb_raw_order partition(p3);

1. 分区执行计划

explain partitions SELECT * FROM testdb2.tb_raw_order ;
explain partitions SELECT * FROM testdb2.tb_raw_order partition(p0);

1. 更改表分区定义

Alter table testdb2.tb_raw_order  partition by hash(order_id)partitions 7;
Alter table testdb2.tb_raw_order  partition by hash(order_id)partitions 4;

1. 创建函数生成随机字符串

DROP FUNCTION IF EXISTS rand_string;
CREATE FUNCTION rand_string(n INT)
RETURNS VARCHAR(255)
BEGIN
DECLARE chars_str varchar(100) DEFAULT 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
DECLARE return_str varchar(255) DEFAULT '';
DECLARE i INT DEFAULT 0;
WHILE i < n DO
SET return_str = concat(return_str,substring(chars_str , FLOOR(1 + RAND()*62 ),1));
SET i = i +1;
END WHILE;
RETURN return_str;
END;

SELECT rand_string(10);

SHOW FUNCTION STATUS WHERE DB = 'testdb2';

1. 创建存储过程生成测试数据

DROP PROCEDURE IF EXISTS load_tb_raw_orders;
CREATE PROCEDURE load_tb_raw_orders ( )
BEGIN
DECLARE v INT DEFAULT 0;
DECLARE alphabet varchar(100) DEFAULT 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
WHILE v < 800000 DO
INSERT INTO tb_raw_order(buyer_id, total_amount)
VALUES
(concat_ws('_', 'John', rand_string(3)),  rand( v ) * 10000);
SET v = v + 1;

END WHILE;
END;

DROP PROCEDURE IF EXISTS load_tb_raw_orders_np;
CREATE PROCEDURE load_tb_raw_orders_np ( )
BEGIN
DECLARE v INT DEFAULT 0;
DECLARE alphabet varchar(100) DEFAULT 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
WHILE v < 800000 DO
INSERT INTO tb_raw_order_np(buyer_id, total_amount)
VALUES
(concat_ws('_', 'John', rand_string(3)),  rand( v ) * 10000);
SET v = v + 1;

END WHILE;
END;

1. 调用存储过程

TRUNCATE TABLE  tb_raw_order;
call load_tb_raw_orders();
SELECT * FROM tb_raw_order;

SELECT RAND( ), RAND( ), RAND( );
SELECT RAND( 2), RAND( 4), RAND( 6);

TRUNCATE TABLE  tb_raw_order_np;
CALL load_tb_raw_orders_np();
SELECT * FROM tb_raw_order_np;

SELECT count(*) FROM tb_raw_order_np WHERE mod(order_id, 4) = 0
SELECT count(*) FROM tb_raw_order PARTITION(p0) WHERE mod(order_id, 4) = 0

1. 查询性能比较

SHOW processlist
SELECT @@profiling

SHOW PROFILES;
SHOW PROFILE FOR QUERY <query id>

SELECT * FROM INFORMATION_SCHEMA.PROFILING WHERE query_id = 95;

SHOW VARIABLES LIKE '%slow_query_log%';
SET GLOBAL slow_query_log = 1;

高级特性

1. 子查询使用Partition

SELECT
t1.*
FROM
tb_raw_order PARTITION(p0)  AS t1 ,
( SELECT order_id FROM tb_raw_order PARTITION(p0) WHERE buyer_id LIKE 'John_%' ORDER BY order_id DESC LIMIT 2000000, 10 ) AS t2
WHERE
t1.order_id = t2.order_id;

EXPLAIN SELECT
*
FROM
tb_raw_order
WHERE
buyer_id LIKE 'John_%'
ORDER BY
order_id DESC
LIMIT 2000000,
10;

EXPLAIN
SELECT
t1.*
FROM
tb_raw_order PARTITION(p0)  AS t1 ,
( SELECT order_id FROM tb_raw_order PARTITION(p0) WHERE buyer_id LIKE 'John_%' ORDER BY order_id DESC LIMIT 2000000, 10 ) AS t2
WHERE
t1.order_id = t2.order_id;

参考资料

1. MySQL存储过程
2. MySQL表分区
3. M有SQL性能工具简介
4. MySQL官方的分区资料