Re: BUG #15577: Query returns different results when executedmultiple times - Mailing list pgsql-bugs

On Thu, 10 Jan 2019 at 12:28, Thomas Munro
<thomas.munro@enterprisedb.com> wrote:
> Hmm.  Why are those ExecQual() -> false cases not showing up as
> variation in the "Rows Removed by Filter" counter visible in EXPLAIN
> ANALYZE?  Then we might have arrived here a lot faster.
> InstrCountFiltered1(node, 1) is executed, but somehow the count
> doesn't make it into the total shown by EXPLAIN.

Good question.  They are tracked by the instrumentation, it's just
that show_instrumentation_count() divides by nloops so the additional
filtered rows are lost to the rounding.  Removing the / nloops shows
you what you want to see.

-- 
 David Rowley                   http://www.2ndQuadrant.com/
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