mysql将表a中查询的数据插入到表b中 如果表b存在 1 code class=sqlcode class=sqlcode class=sqlinsert into b select * from a;/code/code/code 如果表b不存在 1 code class=sqlcode class=sqlcode class=sqlcode class=sqlcode class=sqlcode class=sqlc
mysql将表a中查询的数据插入到表b中
如果表b存在
1
insert into b select * from a;
如果表b不存在
1
create table b as select * from a;
扩展：
将b表中的某写字段值插入到a表中
1
insert into a (userid,username) select b.userid,b.username from tr_ajax_chat_messages;
将a表和b表userid相等的值保存到a表
1update a set a.username=(select b.username from b where a.userid = b.userid);