mysql分表可以有三種辦法實現:
1.直接物理表實現分割槽 (主要由程式控制);
2.通過merge儲存引擎
3.通過分割槽字段進行分割槽
當然也可以通過上面3種方式進行自由組合
下面的例子說的是第三種-分割槽表:
a--建立分割槽表
create table test_log
(id bigint(20) not null auto_increment,
name varchar(20) null,
gmt_create datetime not null,
primary key (id,gmt_create),
key idx_name (name)
)engine=innodb default charset=utf8
partition by range(to_days(gmt_create))
(partition p20141115 values less than (to_days('2014-11-15')),
partition p20141130 values less than (to_days('2014-11-30')),
partition p20141215 values less than (to_days('2014-12-15')),
partition p20141231 values less than (to_days('2014-12-31')),
partition p20150115 values less than (to_days('2015-01-15')),
partition p20150131 values less than (to_days('2015-01-31')),
partition p20150215 values less than (to_days('2015-02-15')),
partition p20150228 values less than (to_days('2015-02-28')),
partition p20150315 values less than (to_days('2015-03-15')),
partition p20150331 values less than (to_days('2015-03-31')),
partition p20150415 values less than (to_days('2015-04-15')),
partition p20150430 values less than (to_days('2015-04-30'))
);b--新增分割槽
alter table test_log add partition (partition p20150515 values less than (to_days('2015-05-15')));
alter table test_log add partition (partition p20150531 values less than (to_days('2015-05-31')));
alter table test_log add partition (partition p20150615 values less than (to_days('2015-06-15')));
alter table test_log add partition (partition p20150630 values less than (to_days('2015-06-30')));
alter table test_log add partition (partition p20150715 values less than (to_days('2015-07-15')));
alter table test_log add partition (partition p20150731 values less than (to_days('2015-07-31')));
alter table test_log add partition (partition p20150815 values less than (to_days('2015-08-15')));
alter table test_log add partition (partition p20150831 values less than (to_days('2015-08-31')));
alter table test_log add partition (partition p20150915 values less than (to_days('2015-09-15')));
alter table test_log add partition (partition p20150930 values less than (to_days('2015-09-30')));
alter table test_log add partition (partition p20151015 values less than (to_days('2015-10-15')));
c--刪除分割槽
alter table test_log drop partition p20150515;
d--插入資料
insert into test_log
select null,'jack',now()
e-- 指定分割槽查詢
select * from test_log partition(p20150930);
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