Re: extracting from epoch values in pgsql

On Thu, Sep 17, 2009 at 06:34:39PM +0100, Gavin McCullagh wrote:
> On Thu, 17 Sep 2009, Gavin McCullagh wrote:
> 
> > On Thu, 17 Sep 2009, Frank Bax wrote:
> > 
> > > Gavin McCullagh wrote:
> > >> SELECT time, to_timestamp(time) AS ts, 
> > >> EXTRACT('months',to_timestamp(time)) FROM mdl_log;
> > >> ERROR:  syntax error at or near ","
> > >> LINE 1: ...t time, to_timestamp(time) AS ts, extract('months',to_times...
> > >
> > > Try replacing extract('month',value) with extract('months' from value)
> > 
> > Makes no difference whether month or months:
> 
> Actually, I pasted a different query, but based on the one in my last
> email:
> 
> moodle-01-01-2009=# SELECT EXTRACT('months',(TIMESTAMP WITH TIME ZONE 'epoch' + mdl_log.time * INTERVAL '1 second'))
> FROM mdl_log;
> ERROR:  syntax error at or near ","
> LINE 1: SELECT EXTRACT('months',(TIMESTAMP WITH TIME ZONE 'epoch' + ...
>                                ^
> moodle-01-01-2009=# SELECT EXTRACT('month',(TIMESTAMP WITH TIME ZONE 'epoch' + mdl_log.time * INTERVAL '1 second'))
> FROM mdl_log;
> ERROR:  syntax error at or near ","
> LINE 1: SELECT EXTRACT('month',(TIMESTAMP WITH TIME ZONE 'epoch' + m...
>                               ^
> 
> Gavin
> 
Gavin,

I think Frank had the answer:

Try replacing extract('month',value) with extract('months' from value)

Look at the documentation for the syntax for further details.

Regards,
Ken