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5_2007-2008 String Manipulation #182433

In-Memory SQL Engine

Wouldn't it be nice if you could use good-ole SQL language to execute a Select statement against a set of locally-cached DataTables that you've already retrieved from an underlying database? This class does exactly that... it supports a minimal set of SQL SELECT command statements against a group of ADO.Net DataTables contained in a detached DataSet. The purpose is to prevent a round trip to the server to accomplish simple things like what is available with the JOIN and GROUP BY clauses of the SELECT command. The syntax for the SELECT command is designed around the SQL Server 2000 dialect of the SQL language. What's supported is SQL statements like the following: SELECT Categories.CategoryID, CategoryName, AVG(UnitsInStock) AS AvgUnits FROM Products JOIN Categories ON Categories.CategoryID = Products.CategoryID WHERE (UnitsInStock > 0) AND (Discontinued = 0) GROUP BY Categories.CategoryID, CategoryName HAVING (AVG(UnitsInStock) > 30) ORDER BY AvgUnits DESC

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