Re: enable_joinremoval

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Robert Haas <robertmhaas(at)gmail(dot)com>
Cc: Simon Riggs <simon(at)2ndquadrant(dot)com>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: enable_joinremoval
Date: 2010-03-29 15:46:55
Message-ID: 14201.1269877615@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> OK, I'll write a patch for that; and a consensus emerges that we
> should also have enable_joinremoval, then I will add that as well. I
> think the only argument for NOT having enable_joinremoval is that you
> can always modify the query to say SELECT * rather than some more
> specific SELECT list,

Uh, no, the argument for not having enable_joinremoval is that it's
useless.

In particular, I categorically deny the argument that putting it in will
reduce user confusion. If anyone is confused because EXPLAIN shows that
some table isn't getting joined to, you think that the fact that
somewhere in the manual is a mention of enable_joinremoval will
un-confuse them? If they knew that switch was there or what it did,
they wouldn't be confused to begin with.

regards, tom lane

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2010-03-29 15:55:03 Re: enable_joinremoval
Previous Message Jaime Casanova 2010-03-29 15:42:33 Re: enable_joinremoval