sum(time) problem

Hi all,

I've got following table structure:

sport=# \d polar                Table "polar"Column |           Type           | Modifiers
--------+--------------------------+-----------ts     | timestamp with time zone | not nulltime   | time without time
zone  |sport  | integer                  | default 1kcal   | integer                  |
 
Primary key: polar_pkey

sport=# select * from polar limit 3;          ts           |   time   | sport | kcal
------------------------+----------+-------+------2001-05-17 19:47:31+02 | 00:28:25 |     1 |  3882001-05-18
17:08:11+02| 00:42:36 |     1 |  5952001-05-19 13:41:43+02 | 00:51:39 |     1 |  737
 
(3 rows)


I'd like to have the total amount of time:

sport=# select sum(time) from polar where extract(year from ts)=2001;
ERROR:  Unable to select an aggregate function sum(time without time zone)

It seems I've chosen the wrong type. Or is there another solution?

Oliver


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