Wanted: Forced Parallelism

James Anderson would like a query hint to force parallelism:

I would like to see a hint that causes the optimiser to consider a parallel plan no matter the cost of the query. It’s possible to get this behaviour with trace flag 8649 but it’s unsupported by Microsoft and therefore unfit for production use.

I only tend to use query hints as a very last resort. It’s almost always better to allow the optimiser to make these decisions and continue to reevaluate these decisions as your data changes but sometimes they can be a get out of jail free card.

I’ve written about this before and so has Paul White. Paul created this connect item for something similar. Please vote it up if you think it could help with your query tuning.

Click through for the full argument, and then hit the Connect item if you agree.

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