sql語句跨數據庫的表聯接

直接使用 數據庫名.表名來聯接

以mysql爲例 說明跨數據庫的表聯接

1、 數據庫 db1 表 tb1(uid,username,groupname)
2、數據庫 db2 表 tb2(uid,phone,addr)

現在要聯接tb1和tb2兩張表

select a.uid as uid ,a.username as uname ,a.groupname as group,b.phone as phone,b.addr as addr
from db1.tb1 as a db2.tb2 as b
where a.uid = b.uid;