From: Tom Lane <tgl@sss.pgh.pa.us>
To: Vik Fearing <vik.fearing@2ndquadrant.com>
Cc: Andrew Gierth <andrew@tao11.riddles.org.uk>
Cc: pgsql-hackers@postgresql.org
Subject: Re: Fix for FETCH FIRST syntax problems
Date: Sat, 19 May 2018 19:41:10 -0400
Message-ID: <25267.1526773270@sss.pgh.pa.us> (raw)
In-Reply-To: <03da97fc-9d6b-cbe1-c28f-cee7c1ba5c38@2ndquadrant.com>
References: <877enz476l.fsf@news-spur.riddles.org.uk>
<22981.1526770675@sss.pgh.pa.us>
<03da97fc-9d6b-cbe1-c28f-cee7c1ba5c38@2ndquadrant.com>
Vik Fearing <vik.fearing@2ndquadrant.com> writes:
> On 20/05/18 00:57, Tom Lane wrote:
>> Also, why'd you back off "must write" to "should write" in the docs?
>> This doesn't make the parens any more optional than before.
> It certainly does. It allows this now:
> PREPARE foo AS TABLE bar FETCH FIRST $1 ROWS ONLY;
No, it makes the parens omittable in the cases specified in the previous
sentence. The sentence I'm complaining about is describing other cases,
in which they're still required.
> I'm +1 for backpatching it. It may be operating as designed by PeterE
> ten years ago, but it's not operating as designed by the SQL standard.
By that argument, *anyplace* where we're missing a SQL-spec feature
is a back-patchable bug. I don't buy it.
It may be that this fix is simple and safe enough that the risk/reward
tradeoff favors back-patching, but I think you have to argue it as a
favorable tradeoff rather than just saying "this isn't per standard".
Consider: if Andrew had completely rewritten gram.y to get the same
visible effect, would you think that was back-patchable?
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-hackers@postgresql.org
Cc: tgl@sss.pgh.pa.us, vik.fearing@2ndquadrant.com, andrew@tao11.riddles.org.uk
Subject: Re: Fix for FETCH FIRST syntax problems
In-Reply-To: <25267.1526773270@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox