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Is there any way to force bitmap filter operator in a three table inner join. the query is running is parallel and i have a where clause in it which filter about half of the rows from one table but i dont see a bitmap filter operator.

I couldnt find any query hints for it, just wondering if there is any other way of testing a query plan with a bitmap operator?

jesijesi
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  • What join types are you getting? It is only possible to get bitmap filters for hash join or a merge join with a blocking operator before it. – Martin Smith Jul 13 '16 at 20:57
  • I am getting a hash join. – jesijesi Jul 13 '16 at 20:58
  • I don't know of any hints myself. Maybe you could tackle it from another angle. How accurate are the estimated vs actual rows? Is the issue that SQL Server doesn't think the filtering will be very selective? – Martin Smith Jul 13 '16 at 21:05
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    TF 7359,7497, 7948 all apparently *disable* various types of bitmap filtering (and perhaps have other side effects). Maybe there is one to force it where possible but I can't find anyone ever writing about it. – Martin Smith Jul 13 '16 at 21:42

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