Re: [SQL] Finding the "most recent" rows

I don't think you can be using 6.5 even if you think you are. Make sure
you have 6.5 and everything is pointing to 6.5 including postmaster.


Chairudin Sentosa wrote:
> 
> I tried this, and did not work.
> 
> ibs=> select * from ibs_billing_record order by start_time desc limit 2;
> ERROR:  parser: syntax error at or near "limit"
> 
> Regards,
> Chai
> 
> Michael J Davis wrote:
> 
> > Try
> > select * from the_place order by the_time desc limit 2;
> >
> >         -----Original Message-----
> >         From:   Chris Bitmead [SMTP:chris.bitmead@bigfoot.com]
> >         Sent:   Thursday, April 22, 1999 8:45 AM
> >         To:     pgsql-sql@postgresql.org
> >         Subject:        Re: [SQL] Finding the "most recent" rows
> >
> >         Try
> >         SELECT the_place, max(the_time) FROM the_place GROUP BY the_place;
> >
> >         Julian Scarfe wrote:
> >         >
> >         > I have a table (representing a set of observations) with datetime
> > fields and a
> >         > non-unique place field.
> >         >
> >         > e.g.
> >         > create table obs (
> >         > the_time datetime,
> >         > the_place char(8),
> >         > ...other fields...
> >         > )
> >         >
> >         > I'd like an efficient way to pull out the most recent row (i.e.
> > highest
> >         > datatime) belonging to *each* of a number of places selected by a
> > simple
> >         > query.
> >         >
> >         > e.g. given a table such as:
> >         >
> >         > the_time    the_place   ...
> >         > 0910        London
> >         > 1130        London
> >         > 0910        Paris
> >         > 0930        London
> >         > 0840        Paris
> >         > 1020        London
> >         > 0740        Paris
> >         >
> >         > I'd like to select:
> >         > 1130        London
> >         > 0910        Paris
> >         >
> >         > Most of my attempts at this (as an SQL novice) feel very clumsy
> > and
> >         > inefficient. Is there an efficient way of doing this in SQL?
> >         > --
> >         >
> >         > Julian Scarfe
> >
> >         --
> >         Chris Bitmead
> >         http://www.bigfoot.com/~chris.bitmead
> >         mailto:chris.bitmead@bigfoot.com