mysql 表分区
1.查:看表emp是否分区了
select
partition_name part,
partition_expression expr,
PARTITION_METHOD,
partition_description descr,
table_rows
from information_schema.partitions where
table_schema = schema()
and table_name='emp';
2.删:会将该分区里面的数据一并删除
alter table emp drop partition p1;
2.1删除表的分区 (不会删除数据)
Alter table emp remove partitioning;
3.对现有表增加分区 (比较耗内存,会先复制表再创建分区,再insert数据)
ALTER TABLE emp PARTITION BY RANGE (YEAR(birthdate))
(
PARTITION p_1 VALUES LESS THAN (1980),
PARTITION p_2 VALUES LESS THAN (1990),
PARTITION p_3 VALUES LESS THAN MAXVALUE );
4.对比加分区和不加的情况
deliveryorderp 和 deliveryorder表结构和数据都完全一样
select * from deliveryorderp where id = '5737462120';
结果显示加分区的deliveryorderp比不加分区快很多