normally I script it like this: update t2 set total = t1.qty * 0.13 from table2 as t2 join table1 as t1 on t1.tbl1Id = t2.tbl1Id where t1.SaleDate > '20121012' and t1.Model = 'AAA'
But in this case you can also take the other conditions into to the ON clause: update t2 set total = t1.qty * 0.13 from table2 as t2 join table1 as t1 on t1.tbl1Id = t2.tbl1Id and t1.SaleDate > '20121012' and t1.Model = 'AAA'