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HomeDatabaseMysql TutorialMySQL中create table as 与like的区别分析_MySQL

本文分析了MySQL中create table as 与like的区别。分享给大家供大家参考,具体如下:

对于mysql的复制相同表结构方法,有create table as 和create table like 两种,区别是什么呢?

代码如下:

create table t2 as select * from t1 where 1=2;

或者

代码如下:

limit 0;


as创建出来的t2表(新表)缺少t1表(源表)的索引信息,只有表结构相同,没有索引。

代码如下:

create table t2 like t1 ;


like 创建出来的新表包含源表的完整表结构和索引信息

二者的用途:

as用来创建相同表结构并复制源表数据

like用来创建完整表结构和全部索引

oracle支持as,也是只有表结构没有索引
oracle不支持like。

希望本文所述对大家MySQL数据库设计有所帮助。

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