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From: David Rowley <[email protected]>
To: [email protected]
Subject: pgsql: Clarify the 'rows' parameter in create_append_path
Date: Thu, 15 Feb 2024 00:13:50 +0000
Message-ID: <[email protected]> (raw)

Clarify the 'rows' parameter in create_append_path

This is extracted from a larger patch to improve the UNION planner.
While working on that, I found myself having to check what the 'rows'
parameter is for.  It's not obvious that passing a negative number is the
way to have the rows estimate calculated and to find that out you need
to read code in create_append_path() and in cost_append().

Discussion: https://postgr.es/m/CAApHDvpb_63XQodmxKUF8vb9M7CxyUyT4sWvEgqeQU-GB7QFoQ@mail.gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/87027cb55bf7b33416880f7f5f5e67f4202d5881

Modified Files
--------------
src/backend/optimizer/util/pathnode.c | 4 ++++
1 file changed, 4 insertions(+)

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