mysql group?

[garfx]

hello

i have a table or orders looks like the following

id itemID customerID date qty
1 4 3 2009-04-04 100
2 4 3 2009-04-04 200
3 4 2 2009-04-05 2500
4 4 2 2009-04-06 1000
5 4 2 2009-04-06 1000

i wish to merger the customerID together and add the qty's so you get the following:

itemID customerID qty
4 3 300
4 2 4500

i can manage this using query within a query but is there a more efficent way?

please help Gareth

[laserlight]

I usually need to check my SQL as I lack practice, but you can try:

SELECT itemID, customerID, SUM(qty) FROM orders GROUP BY customerID