Re: Why PG uses nested-loop join when no indexes are available?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: David Grelaud <dgrelaud(at)ideolys(dot)com>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Why PG uses nested-loop join when no indexes are available?
Date: 2016-01-13 15:02:38
Message-ID: 29747.1452697358@sss.pgh.pa.us
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David Grelaud <dgrelaud(at)ideolys(dot)com> writes:
> Statistics are not propagated when Common Table Expressions (CTE) are used.
> The cardinality of a CTE is equal to 1 most of the time

Really?

The rest of this seems to be proceeding from completely false assumptions.

regards, tom lane

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