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sql之表连接和group by +组函数的分析

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Release: 2016-06-07 17:37:44
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1、首先我们来先看一个简单的例子: 有[Sales.Orders]订单表和[Sales.Customers]顾客表,表的机构如下 业务要求:筛选 来自按时打算国家的用户以及所下的订单数 o.custid,o c 4 on o.custid = c.custid o.custid;

1、首先我们来先看一个简单的例子:

有[Sales.Orders]订单表和[Sales.Customers]顾客表,表的机构如下

业务要求:筛选  来自“按时打算”国家的用户以及所下的订单数

o.custid,o c 4 on o.custid=c.custid o.custid; ,

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