Re: Problems with avg on interval data type

pgsql-bugs@postgresql.org writes:
> The query does an avg on an interval column and now gets the error:
> ERROR:  Bad interval external representation '0'

Sorry about that :-(.  A last-minute tightening of the allowed input
formats for interval broke avg(interval), but you're the first one to
notice.

I have corrected this in the sources for 7.1.2, but that will not help
you much unless you care to re-initdb with 7.1.2.  If you don't want to
initdb, you can manually correct the erroneous catalog entry with

update pg_aggregate set agginitval = '{0 second,0 second}' where
aggname = 'avg' and aggbasetype = 1186;

Note you will need to do this in each extant database including
template1 (or at least all the databases where you plan to use
avg(interval)).

            regards, tom lane