在CI中连接两个表

Question

我有两个表poolRequests和users poolRequests包含列 - ＆gt; fromId（用户id），风湿（用户ID），的RequestType（1/2） 用户包含列 - ＆gt; userId，name

现在我需要加入这两个表，如

select users.id ,users.name from users
if requestType=1
join poolRequests on users.userId= poolRequests.fromId  
if requestType=2
join poolRequests on users.userId= poolRequests.toId

Answer 1

试试这个：

select users.id ,users.name
from users
join poolRequests
on (requestType = 1 and users.userId= poolRequests.fromId)  
or (requestType = 2 and users.userId= poolRequests.toId)