How do I solve this efficiently?

Hi,

I have a table like the following :
Table "expenses"
Attribute | Type | Modifier
-----------+-------------+----------
datum | date |
ware | varchar(80) |
price | float4 |

To get a summary of what I spent in a month I do a:
select ware,sum(price) from ausgaben where datum >= '1-1-2000' and datum <
'2-1-2000';

Now I would like to have an overview for a year in the form:

Ware January February March ...
Food 50.0 40.0 60.0
CDs. 20.0 40.0

.....

What's the easiest way of doing this?
I would like to avoid creating to many temporary tables if possible.

Konstantin

--
Dipl-Inf. Konstantin Agouros aka Elwood Blues. Internet: elwood(at)agouros(dot)de
Otkerstr. 28, 81547 Muenchen, Germany. Tel +49 89 69370185
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