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Subqueries and derived queries

Posted By:      Posted Date: October 15, 2010    Points: 0   Category :Sql Server

I work with SQL Server 2008

I have a question: Is it possibility of using "group by" or "order by " in subqueries? Why can I not do it? And what are variants for these situation?

I have a task. I have Orders table with fields below. I need return the three most recent orders for each customer.

custid      orderid     orderdate
----------- ----------- -----------------------

The result should be get with using derived query

custid      orderid     orderdate
----------- ----------- -----------------------

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Msg 1033, Level 15, State 1, Line 11
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