SQL Row # within group

Good morning, folks,

I am trying to find out how to do the following without having to jump through coding loops to get there.
I need to come up with an SQL statement that generates a sequence number (1, 2, 3, etc) (aka "row number") within a group of records having the same (composite) key value, with separate numbering within each key value group.

For example, from the following:


K1 K2 data

1 ABC ...
1 DEF ...
1 GHI ...
2 any ...
2 more ...
3 justone
4 xyz


Output would look like this, generated row numbers within groups of K1 values:

K1 K2 data row#

1 ABC ... 1
1 DEF ... 2
1 GHI ... 3

2 any ... 1
2 more ... 2

4 xyz ... 1

I've looked at the IBM I documentation and done a search and the closest I came up to what I need is here:
http://archive.midrange.com/midrange-l/201505/msg00438.html

And I found the SQL reference for this row-number() clause, but it has nothing about row numbers within a group value (or "group partition")

select row_number() over (order by colb asc) as number,
cola, colb, colc
from qtemp.mytable
where cola is not null
order by colb
NUMBER COLA COLB COLC
1 B 2 3
2 A 65 1
3 D 72 2
4 C 101 4



Alan Cassidy
Softare Engineer
Direct Phone - 954-693-0000 Ext. 3433
ACassidy@xxxxxxxxxxxxxx<mailto:ACassidy@xxxxxxxxxxxxxx>
www.hppartners.com<http://www.hppartners.com/>

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