simple problem???

Dear users....
It's a simple problem I think (and I hope :-)

I have a table like this:
A|B|C
1|2|20
1|3|10
1|4|21
2|3|12
2|4|22
3|4|23

where the first two column are a combination without repetition (with
k=2) of the numbers 1,2,3,4
for each pair I have a value in the column C.

I would want a select that can extract these records:

1|3|10
2|3|12
3|4|23

i.e. the select must look into the A field first and:
-select all records where A=1,
-find, into this selection, the record where there's the minimum value
of the field C
-print all the fields for this record.

then

-select all records where A=2
-find, into this selection, the record where there's the minimum value
of the field C
-print all the fields of this record.

and so on...

using
SELECT a,MIN(c) FROM table GROUP BY a

is a partial solution because I can't see the value of B
and I obtain:

1|10
2|12
3|23

How can I do for plotting also the value of B???

Thank you very much

Ivan

--
Ivan Marchesini
Department of Civil and Environmental Engineering
University of Perugia
Via G. Duranti 93/a
06125
Perugia (Italy)
e-mail: marchesini(at)unipg(dot)it
ivan(dot)marchesini(at)gmail(dot)com
tel: +39(0)755853760
fax: +39(0)755853756
jabber: geoivan73(at)jabber(dot)org