Using CROSS APPLY in SQL Server 2005
My interest in writing this article was started by an MSDN article titled SQL Server 2005: The CLR Enters the Relational Stage. The article shows how to write a function that returns the top three countries per category. That's always been something that was difficult to do in SQL so I was curious about the approach. The article started out well but I was very unhappy by the end. It's just soooo much easier to do this in SQL Server 2005 using the new CROSS APPLY clause in Transact-SQL. So I'm going to write a query to return the top 3 orders for each customer and I'm going to do it in about 10 lines of SQL. (UPDATE: An alert reader found an even better approach!)
2005-06-02
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