Re: explain plan, can you explain this?

From: John Kanagaraj <>
Date: Wed, 9 Jan 2008 20:08:49 -0800
Message-ID: <>


> The very interesting part is that in a one-hour statspack, this statement
> generates 30 mil buffer gets, executed 111,388 times (about 273 buffer gets
> per exec). When combined with the facts below, it becomes a puzzler:

This is only slightly related to the issue, but STATSPACK's SQL is a capture of V$SQL "as-is" when the snapshot took place. SPREPORT does NOT perform a Diff as it does with other stats (i.e. end_stat - begin_stat). The 111,388 executions is *cumulative* since that SQL was last loaded/parsed. This is apparent if you look at the STATSPACK source at $OH/rdbms/admin/spcpkg.sql.

You should look at Tim G's "sphistory.sql" to determine the periodic progression of execution and other stats for a given SQL.

John Kanagaraj <><
DB Soft Inc (Sorry - not an Oracle blog!)
** The opinions and facts contained in this message are entirely mine
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Received on Wed Jan 09 2008 - 22:08:49 CST

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