2015
04-26
04-26
多表数据连接 Left join
一个我写的实例:其中多表连接,一共连接了3个表。使用聚集函数SUM,用到了GROUPBYSELECT a.[UserID],b.[Name],sum (c.[Money]+c.[Bank])as TotalMoneyFROM Table1 a(nolock) LEFT JOIN Table2 b(nolock) on a.[UserID] = b.[UserID] LEFT JOIN Table3 c(nolock) ON b.[UserID]=c.[UserID] WHERE a.[Use...
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