Thread: Analyzing last run query in psql

Joe Van Dyk <joe@tanga.com> wrote:

> I frequently need to analyze the last query in psql:
>     select * from table where id = 1;
>     explain analyze select * from table where id = 1;
>
> It would be nice to be able to do this:
>     explain analyze $LAST
>
> (or can I do something like that already?)
>
> I'm not using psql interactively, I pipe files into psql (if it matters).

There is no history or something like that, but you can use autoexplain.
http://www.postgresql.org/docs/9.2/interactive/auto-explain.html




Andreas
--
Really, I'm not out to destroy Microsoft. That will just be a completely
unintentional side effect.                              (Linus Torvalds)
"If I was god, I would recompile penguin with --enable-fly."   (unknown)
Kaufbach, Saxony, Germany, Europe.              N 51.05082°, E 13.56889°

On Wed, Jul 3, 2013 at 7:05 AM, Joe Van Dyk <joe@tanga.com> wrote:
> I frequently need to analyze the last query in psql:
>     select * from table where id = 1;
>     explain analyze select * from table where id = 1;
>
> It would be nice to be able to do this:
>     explain analyze $LAST
>
> (or can I do something like that already?)
>
> I'm not using psql interactively, I pipe files into psql (if it matters).


I don't know of any feature like that, but maybe you can do the
following in your script/files:

\set lastquery 'your-query-here'

so that you can do something like

explain :lastquery;

But if you are able to manipulate your scripts you can just insert the
explain by hand on queries you are interested in, or use autoexplain
for all the queries.

Luca

It was my dream to have something we already have in shell -

explain analyze !$

I think it should be not very difficult.

Oleg
On Tue, 2 Jul 2013, Joe Van Dyk wrote:

> I frequently need to analyze the last query in psql:
>    select * from table where id = 1;
>    explain analyze select * from table where id = 1;
>
> It would be nice to be able to do this:
>    explain analyze $LAST
>
> (or can I do something like that already?)
>
> I'm not using psql interactively, I pipe files into psql (if it matters).
>
> Joe
>

     Regards,
         Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
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