Re: IDLE in transaction introspection

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>

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

Cc: Robert Haas <robertmhaas@gmail.com>, Magnus Hagander <magnus@hagander.net>, Scott Mead <scottm@openscg.com>, pgsql-hackers <pgsql-hackers@postgresql.org>

Date: 2011-11-01T14:04:06Z

Lists: pgsql-hackers

On Tue, Nov 1, 2011 at 1:52 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
>> Why not leave it exactly as it is, and add a previous_query column?
>
>> That gives you exactly what you need without breaking anything.
>
> That would cost twice as much shared memory for query strings, and twice
> as much time to update the strings, for what seems pretty marginal
> value.  I'm for just redefining the query field as "current or last
> query".  I could go either way on whether to rename it.

That's a good reason.

> If anyone's really hot about backward compatibility, it would not be
> very hard to create a view that replicates the old behavior working
> from a "state" column and a current-or-last-query column.

I'm in favour of change, when that has a purpose, just like you.

-- 
 Simon Riggs                   http://www.2ndQuadrant.com/
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