RE: forming a dynamic query – SQLServerCentral

SSC Guru

Points: 186127

May 6, 2014 at 2:04 am

You have three options: dynamic sql, a catch-all query, or using IF blocks to test the parameters and run whichever query fits the parameters.

Catch-all queries are popular but come with a cost, which you can read about here[/url].

Using IF blocks is almost always the most performant method but you then have to maintain a number of queries each differing only in the WHERE clause.

Dynamic sql can certainly deal with your requirement but usually require a little more work than the other two methods. Try composing the different queries corresponding to the different parameters, something like your last post but with real column and table names, then use this as a template for building and testing your dynamic sql. Test each piece using PRINT.

^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}

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