Common Table Expressions (CTEs) can help improve the readability (and thus the maintainability) of SQL statements without compromising performance. They also make writing recursive code in T-SQL significantly easier than it was in previous versions of SQL Server.
In the October issue of MSDN Magazine, John Papa begins by describing how CTEs work and what scenarios they can be used to address, then discusses the advantages of using CTEs versus using traditional T-SQL constructs, such as derived tables, views, and custom procedures.
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