Horton

Re: Implement targetlist SRFs using ROWS FROM() (was Changed SRF in targetlist handling)

Kevin Grittner <kgrittn@gmail.com>

View thread View on postgr.es
From: Kevin Grittner <kgrittn@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>, Robert Haas <robertmhaas@gmail.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2016-09-02T15:01:39Z
Lists: pgsql-hackers 
On Fri, Sep 2, 2016 at 9:51 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> regression=# select *, generate_series(1,3) from int8_tbl;

I'm sure that you realize that running a query of that form twice
against a table with more than one heap page could result in rows
in a different order, even if no changes had been made to the
database (including no vacuum activity, auto- or otherwise).  If
someone reported that as a bug, what would we tell them?

--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

Commits

  1. Remove obsoleted code relating to targetlist SRF evaluation.

  2. Doc: improve documentation of new SRF-in-tlist behavior.

  3. Move targetlist SRF handling from expression evaluation to new executor node.

  4. Don't split up SRFs when choosing to postpone SELECT output expressions.