Re: how to "group" several records with same timestamp into one line?

zxo102 ouyang wrote:

> I would like to "group" them into one line with SQL like
>
>    1.5     MPa   2.5    M3  3.5  M3   4.5   t   2008-11-12 12:12:12

Look up the "GROUP BY" clause.

http://www.postgresql.org/docs/current/static/sql-select.html

Note that with timestamps you may have to truncate/round them to the
desired precision, since current versions of PostgreSQL store timestamps
in a floating point format and two timestamps you'd expect to be equal
may not end up being seen as exactly equal.

--
Craig Ringer