一、表分区介绍
1.1、简单介绍
1）表分区是将一个表的数据按照一定的规则水平划分为不同的逻辑块，并分别进行物理存储，这个规则就叫做分区函数，可以有不同的分区规则
2）通过show plugins语句查看当前MySQL是否支持表分区功能
mysql> show plugins; +----------------------------+----------+--------------------+---------+---------+ | Name | Status | Type | Library | License | +----------------------------+----------+--------------------+---------+---------+ | binlog | ACTIVE | STORAGE ENGINE | NULL | GPL | | mysql_native_password | ACTIVE | AUTHENTICATION | NULL | GPL | | sha256_password | ACTIVE | AUTHENTICATION | NULL | GPL | | PERFORMANCE_SCHEMA | ACTIVE | STORAGE ENGINE | NULL | GPL | | MRG_MYISAM | ACTIVE | STORAGE ENGINE | NULL | GPL | | MEMORY | ACTIVE | STORAGE ENGINE | NULL | GPL | | InnoDB | ACTIVE | STORAGE ENGINE | NULL | GPL | | INNODB_TRX | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_LOCKS | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_LOCK_WAITS | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_CMP | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_CMP_RESET | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_CMPMEM | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_CMPMEM_RESET | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_CMP_PER_INDEX | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_CMP_PER_INDEX_RESET | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_BUFFER_PAGE | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_BUFFER_PAGE_LRU | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_BUFFER_POOL_STATS | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_TEMP_TABLE_INFO | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_METRICS | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_FT_DEFAULT_STOPWORD | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_FT_DELETED | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_FT_BEING_DELETED | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_FT_CONFIG | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_FT_INDEX_CACHE | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_FT_INDEX_TABLE | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_TABLES | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_TABLESTATS | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_INDEXES | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_COLUMNS | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_FIELDS | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_FOREIGN | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_FOREIGN_COLS | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_TABLESPACES | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_DATAFILES | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | INNODB_SYS_VIRTUAL | ACTIVE | INFORMATION SCHEMA | NULL | GPL | | CSV | ACTIVE | STORAGE ENGINE | NULL | GPL | | MyISAM | ACTIVE | STORAGE ENGINE | NULL | GPL | | ARCHIVE | ACTIVE | STORAGE ENGINE | NULL | GPL | | partition | ACTIVE | STORAGE ENGINE | NULL | GPL | #表分区是支持的 | BLACKHOLE | ACTIVE | STORAGE ENGINE | NULL | GPL | | FEDERATED | DISABLED | STORAGE ENGINE | NULL | GPL | | ngram | ACTIVE | FTPARSER | NULL | GPL | +----------------------------+----------+--------------------+---------+---------+
3）MySQL5.7社区版本的表分区功能是默认开启的
1.2、创建一个表分区示例
#创建分区表
CREATE TABLE employees (
id INT NOT NULL,
fname VARCHAR(30),
lname VARCHAR(30),
hired DATE NOT NULL DEFAULT '1970-01-01',
separated DATE NOT NULL DEFAULT '9999-12-31',
job_code INT NOT NULL,
store_id INT NOT NULL )
PARTITION BY RANGE (store_id) #根据store_id范围分区
( PARTITION p0 VALUES LESS THAN (6), PARTITION p1 VALUES LESS THAN (11),
PARTITION p2 VALUES LESS THAN (16), PARTITION p3 VALUES LESS THAN (21) );
#查看表分区结构
mysql> show create table employees\G
*************************** 1. row ***************************
Table: employees
Create Table: CREATE TABLE `employees` (
`id` int(11) NOT NULL,
`fname` varchar(30) DEFAULT NULL,
`lname` varchar(30) DEFAULT NULL,
`hired` date NOT NULL DEFAULT '1970-01-01',
`separated` date NOT NULL DEFAULT '9999-12-31',
`job_code` int(11) NOT NULL,
`store_id` int(11) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8
/*!50100 PARTITION BY RANGE (store_id)
(PARTITION p0 VALUES LESS THAN (6) ENGINE = InnoDB,
PARTITION p1 VALUES LESS THAN (11) ENGINE = InnoDB,
PARTITION p2 VALUES LESS THAN (16) ENGINE = InnoDB,
PARTITION p3 VALUES LESS THAN (21) ENGINE = InnoDB) */
#插入数据测试
mysql> insert into employees values(1,'a','a',now(),now(),1,1),(2,'b','b',now(),now(),1,6);
#查看
mysql> select * from employees;
+----+-------+-------+------------+------------+----------+----------+
| id | fname | lname | hired | separated | job_code | store_id |
+----+-------+-------+------------+------------+----------+----------+
| 1 | a | a | 2019-10-10 | 2019-10-10 | 1 | 1 |
| 2 | b | b | 2019-10-10 | 2019-10-10 | 1 | 6 |
+----+-------+-------+------------+------------+----------+----------+
mysql> select * from employees partition (p0); #落在第一个分区上store_id<6
+----+-------+-------+------------+------------+----------+----------+
| id | fname | lname | hired | separated | job_code | store_id |
+----+-------+-------+------------+------------+----------+----------+
| 1 | a | a | 2019-10-10 | 2019-10-10 | 1 | 1 |
+----+-------+-------+------------+------------+----------+----------+
mysql> select * from employees partition (p1);
+----+-------+-------+------------+------------+----------+----------+
| id | fname | lname | hired | separated | job_code | store_id |
+----+-------+-------+------------+------------+----------+----------+
| 2 | b | b | 2019-10-10 | 2019-10-10 | 1 | 6 |
+----+-------+-------+------------+------------+----------+----------+