select into from 和 insert into select
select into from 和 insert into select都是用来复制表,
两者的主要区别为:
select into from 要求目标表不存在,因为在插入时会自动创建。
insert into select from 要求目标表存在
备份表数据:
create table emp as select * from scott.emp
还原表数据:
insert into emp select * from scott.emp
1. 复制表结构及其数据:
create table table_name_new as select * from table_name_old
2. 只复制表结构:
create table table_name_new as select * from table_name_old where 1=2;
或者:
create table table_name_new like table_name_old
3. 只复制表数据:
如果两个表结构一样:
insert into table_name_new select * from table_name_old
如果两个表结构不一样:
insert into table_name_new(column1,column2…) select column1,column2… from table_name_old