Horton

Re: Modify the DECLARE CURSOR command tag depending on the scrollable flag

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Boszormenyi Zoltan <zb@cybertec.at>
Cc: Alvaro Herrera <alvherre@2ndquadrant.com>, Michael Meskes <meskes@postgresql.org>, Noah Misch <noah@leadboat.com>, Peter Eisentraut <peter_e@gmx.net>, Robert Haas <robertmhaas@gmail.com>, PG Hackers <pgsql-hackers@postgresql.org>, Heikki Linnakangas <hlinnakangas@vmware.com>, Bruce Momjian <bruce@momjian.us>, Hans-Jürgen Schönig <hs@cybertec.at>
Date: 2013-11-27T18:16:17Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Fix some "translator:" comments mangled by pgindent

  2. Make sure float4in/float8in accept all standard spellings of "infinity".

Boszormenyi Zoltan <zb@cybertec.at> writes:
> 2013-11-23 22:01 keltezssel, Tom Lane rta:
>> Boszormenyi Zoltan <zb@cybertec.at> writes:
>>> Attached is the patch that modified the command tag returned by
>>> the DECLARE CURSOR command. It returns "DECLARE SCROLL CURSOR"
>>> or "DECLARE NO SCROLL CURSOR" depending on the cursor's
>>> scrollable flag that can be determined internally even if neither is
>>> asked explicitly.

>> This does not strike me as an acceptable change.  It will break any code
>> that's expecting the existing command tag, for little or no benefit
>> to most applications.  Even if backwards compatibility were of no concern,
>> I'm not convinced it's a good thing to expose the backend's internal
>> choices about query plans used for cursors, which is what this is
>> basically doing.

> I saw code in the backend allowing a cursor to be scrollable, although
> it was not declared as such. How about ripping that out?

That also fails the unnecessary-backwards-compatibility-break test.

			regards, tom lane