Re: ask about epoch query with datetime

2009/5/7 haries fajar nugroho <hariesfn(at)gmail(dot)com>:
> Hi All,
>
> my institution wants me to migrate from old postgresql to new
> postgresql, but when i test one of the query it failed at query :
> select date_part('epoch',datetime('2009-04-20
> 17:08:01')-datetime('2009-04-20 17:04:24'))::int;
> that query runs well in previous postgresql (PostgreSQL 7.1.3). The
> error message is ERROR:  function datetime("unknown") does not exist
> HINT:  No function matches the given name and argument types. You may
> need to add explicit type casts.
>
> If i read the error message, it means the function has changed or
> something. May  I know the latest function so my query can run well in
> my PostgreSQL 8.1.11 ?

Try something like:

select date_part('epoch','2009-04-20 17:08:01'::TIMESTAMP -
'2009-04-20 17:04:24'::TIMESTAMP)::int;

Ian Barwick