Hop On Your Good Foot
Several weeks back, I blogged about a missed opportunity with the new parameter sensitive plan feature. At the time, I thought that there was indeed sufficient skewness available to trigger the additional plan variants, and apparently some nice folks at Microsoft agreed.
If we step back through the old demo, we’ll get different results.
EXEC dbo.VoteSniffing @VoteTypeId = 4; EXEC dbo.VoteSniffing @VoteTypeId = 2;
I’m not gonna go into a lot of depth here, because I’m writing this while traveling, but we get the (mostly) desired outcome of two different plans being generated. Each plan is more suitable to the amount of data that the query has to process.
I’d consider this a success, even if it adds more queries to the unidentifiable corpse-pile.
Thanks for reading!
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