i have two tables production.product(and sales table and i want to get the total unit

[tigistgetachew]

Production.prod ucttable(produc tid, productcategory , modifieddate and sales table( salesorderid, productid, ,quantity,unitp rice,modifiedda te,orderdate) so i want to get the total amount of unit solid from this two table. How can i write my query?

[Banfa]

SELECT productid, SUM(quantity) FROM sales GROUP BY productid