The Hermit Hacker wrote:
> I can add days to now(), but not subtract?
>
> =====================================
>
> template1=> select now() + '30 days';
> ?column?
> ------------------------------
> Sun Feb 13 22:00:33 2000 AST
> (1 row)
>
> template1=> select now() - '30 days';
> ERROR: Unable to identify an operator '-' for types 'timestamp' and 'unknown'
> You will have to retype this query using an explicit cast
> template1=> select version();
> version
> ---------------------------------------------------------------------
> PostgreSQL 7.0.0 on i386-unknown-freebsd4.0, compiled by gcc 2.95.2
> (1 row)
>
> Marc G. Fournier ICQ#7615664 IRC Nick: Scrappy
> Systems Administrator @ hub.org
> primary: scrappy@hub.org secondary: scrappy@{freebsd|postgresql}.org
>
> ************
Try using standard names (TIMESTAMP instead of now() and INTERVA) as in:
hygea=> select current_timestamp + interval '30 day';
?column?
--------------------------
17/02/2000 16:00:28.00 CET
(1 row)
hygea=> select current_timestamp - interval '30 day';
?column?
--------------------------
19/12/1999 16:00:44.00 CET
(1 row)
hygea=> select now() - '30 day';
ERROR: Unable to identify an operator '-' for types 'timestamp' and 'unknown' You will have to retype this query
usingan explicit cast
José