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 null
time | time without time zone |
sport | integer | default 1
kcal | 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 | 388
2001-05-18 17:08:11+02 | 00:42:36 | 1 | 595
2001-05-19 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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