Re: Problem with extract(epoch from interval ...

On 01/23/2013 03:00 AM, Ian Lawrence Barwick wrote:
> Hi
>
> 2013/1/23 Kaloyan Iliev <kaloyan(at)digsys(dot)bg>:
>> Hi,
>> I have a little problem with extract epoch from interval. It seems that the
>> query works if the interval is in a string but not from DB field.
>> Could someone provide support.
> (...)
>
> You have a casting error; instead of:
>
>> dbr=# SELECT extract(EPOCH FROM INTERVAL b) FROM a;
>> ERROR: syntax error at or near "b"
>> LINE 1: SELECT extract(EPOCH FROM INTERVAL b) FROM a;
>
> use
>
> SELECT extract(EPOCH FROM b::INTERVAL) FROM a;
>
> or
>
>
> SELECT extract(EPOCH FROM CAST (b AS INTERVAL)) FROM a;

Would it not be simpler:

test=> SELECT extract(epoch from b) from a;
date_part
-----------
2592000
7776000
15552000
(3 rows)

As the b field is already an interval.

>
>
> Regards
>
> Ian Barwick
>
>

--
Adrian Klaver
adrian(dot)klaver(at)gmail(dot)com