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SQL Server FAST N Query Hint

Chad Callihan hits the Turbo button:

How familiar are you with the OPTION (FAST N) query hint? It’s not one that I had ever used, so I decided to experiment with it a bit. Let’s look at what it does and how to apply it to a query.

My recollection is that this query hint highly prioritizes “streaming” operators and de-prioritizes operators that work on the whole dataset as a block, such as sorts. This means, for example, that you’ll get more nested loops joins and natural merge joins, but few sort + merge or hash match joins. It may also make some queries take considerably longer as a result.

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