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GianTD 47 posts Joined 11/14
01 Dec 2014
Explain Plan - Final & Other Plan

Hi All !
I usually see this in o/p of Diagnostic Helpstats:
<- END RECOMMENDED STATS FOR FINAL PLAN
BEGIN RECOMMENDED STATS FOR OTHER PLANS ->
 
So, what are Final & Other Plans?
Which stats we should choose for our queries from these two plans?

dnoeth 4628 posts Joined 11/04
02 Dec 2014

This is based on a new feature in TD14.10 named "Incremental Planning and Execution".
Check the SQL Request and Transaction Processing manual for details. 

Dieter

GianTD 47 posts Joined 11/14
02 Dec 2014

Thanks Dieter.
 
Should we use stats recomendations provided under both plans?
 
 

GianTD 47 posts Joined 11/14
02 Dec 2014

What is indicated when difference between Estimated time/Rows and actual time/Rows?
 
Also, how does it matter if Actuals are lower or higher? What they indicate?

dnoeth 4628 posts Joined 11/04
04 Dec 2014

If there's a huge difference between estimated and actual (according to Viewpoint's QueryMonitor or DBQLStepInfoV) stats might be missing or the optimizer couldn't use them or he did a really wrong calculation.
 
If actual is magnitudes higher than estimated this step might have a very bad execution, e.g. seconds estimated, but minutes/hours actual for a Product Join with 100,000 instead of 10 rows.

Dieter

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