备份 一张表到另外一张表

新表存在时

INSERT INTO sys_role_bak(role_name,role_desc) SELECT ROLE_NAME,ROLE_DESC FROM sys_role;

新表不存在时

where 1 =2 select 不会返回任何行，只会有相同的列定义和约束

create table sys_role_bak as select * from sys_role where 1 = 2;

create table sys_role_bak as select * from sys_role;

产生与原表相同的数据表结构，索引和主键 数据需要手动插入

create table sys_role_bak like sys_role;

create table sys_role_bak as select role_name,role_desc from sys_role;