Adding from one sheet to another

[EwatchesUSA]

Hi, can anybody tell us how to set up excel to automatically update quantities from one work sheet to another.
We have work sheet A with part numbers in column A and quantities in column B, in sheet B we keep track of what we sold, sheet B column A has Part numbers and column B has quantity we sold, I need the formula to put in sheet A column B so it updates automatically when we update sheet B, please keep in mind we have more than 10.000 items listed, and numbers can be showing up in sheet B multiple times.
Please advise.

Regards Mike.

 

[jim may]

Expand the 1000 in the formula to accomodate ALL rows..

Excel Workbook
	A	B
1	PartNo	Qty
2	ABC	12
3	BBB	17
4	CCC	19
5	DDD	7
Sheet1

Excel 2007

Cell Formulas
Range	Formula
B2	=SUMIF(Sheet2!$A$2:$A$1000,Sheet1!A2,Sheet2!$B$2:$B$1000)

Excel Workbook
	A	B
1	PartNo	Qty
2	ABC	1
3	BBB	2
4	ABC	3
5	CCC	4
6	BBB	5
7	CCC	6
8	DDD	7
9	ABC	8
10	CCC	9
11	BBB	10
Sheet2

Excel 2007

 

[evnoort]

please ignor

 

[EwatchesUSA]

Thank you, this solved my problem.