多表查询 请求帮助·

Question

select Orders.gameuser, Games.game_name 
from WSS_O_OrderReceive OrderReceive
left join WSS_O_Orders Orders on Orders.OrderID = OrderReceive.OrderReceiveID
left join WSS_G_Games Games on Games.GameID = Orders.GameID
where OrderReceive.receive_gatestate = 1 and OrderReceive.receive_clientstate =2

Answer 1

SELECT  a.gameuser ,
        b.game_name
FROM    ( SELECT    gameid ,
                    gameuser
          FROM      WSS_O_Orders
          WHERE     orderid IN ( SELECT orderreceiveid
                                 FROM   WSS_O_OrderReceive
                                 WHERE  receive_gatestate = 1
                                        AND receive_clientstate = 2 )
        ) a
        INNER JOIN WSS_G_Games b ON a.gameid = b.gameid

Answer 2

试试以下代码：select o.gameuser, g.game_name
from WSS_O_OrderReceive as or
inner join WSS_O_Orders as o on or.orderreceiveid = o.orderid
inner join WSS_G_Games as g on o.gameid = g.gameid
where receive_gatestate = 1
and or.receive_clientstate = 2