test=*# select * from juergen1 ;
s1 | s2 | s3
----+----+----
c | a | 1
c | b | 2
d | a | 3
d | b | 4
(4 rows)
test=*# select s1 as a, min(s3) as b, max (s3) as " " from juergen1 group by s1 order by a;
a | b |
---+---+---
c | 1 | 2
d | 3 | 4
(2 rows)
test=*#