RE: explain plan, can you explain this?

From: Allen, Brandon <>
Date: Fri, 11 Jan 2008 09:34:16 -0700
Message-ID: <04DDF147ED3A0D42B48A48A18D574C4509EBF691@NT15.oneneck.corp>

Andrew, the instances you've seen are normal. I think there is just some confusion here about exactly what we're all trying to say so I'll try to clarify:  

Yes, the statistics values stored in statspack and awr snapshots are cumulative, however the values reported by spreport.sql and awrrpt.sql (or by the "View Report" action under Snapshots in OEM) are the deltas calculated as the difference between those cumulative values for the specified begin and end snapshots.  

For example, at snap #1, we have accumulated 100 phyrds and at snap #10 we have accumulated 1000 phyrds, so when we run spreport or awrrpt and specify beginning snapshot #1 and end snapshot #10, it calculates the delta as 1000-100=900 and reports that 900 phyrds occurred during the interval between whatever time snapshots 1 and 10 were taken.  

Hopefully that makes sense and settles the issue so we can all get along now and enjoy our weekend :-)  


[] On Behalf Of Andrew Kerber

well, unless I have run into 3 really strange instances, it looks like cumulative values to me. Unless you can explain why the phyrds and phywrts are higher for each snap than the previous one for every file in my instance.

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Received on Fri Jan 11 2008 - 10:34:16 CST

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