Re: Are cost estimates based on asserts?

From: "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>
To: <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Are cost estimates based on asserts?
Date: 2005-10-12 23:23:46
Message-ID: s34d54c3.010@gwmta.wicourts.gov
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Hmmm... Poorly phrased question on my part, I guess.

When I saw that the cost estimates tracked so much better
with the actual execution time when the asserts were being
evaluated, it got me wondering whether some significant part
of the costing development and testing occured in that
environment.

I assume we care more about accurate costing in
environments where asserts are not checked, although I
hate to assume anything. If there is a chance that asserts
affected costing calculations, it would give me a vague clue
about where adjustments might be most useful. For a
discussion about a better way to get clues, see my next
post.

-Kevin

>>> Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> 10/12/05 5:15 PM >>>
"Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov> writes:
> [$subject]

No, the planner has no idea about the cost of Asserts.

regards, tom lane

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