Problem Copying records from one table to another?

Hi all,

I have two tables Table1 and Table2. In table one one of the column is delivery Qty and another pick QTY,

Pick qty is editable field i can enter any value. If pick qty is more than del qty i am trhrowing error. upto this is ok.

table1 fields - posnr, matnr , del qty and pick qty.

table2 fields - matnr,pickqty, and some other.

case1

suppose in table1 some line items are there i select all items and isert means i want to insert all recoreds in table2 , here also i ahve to check del qty with pick qty.. This part i done, it is working for me fine.

case 2.

For example Del qty is 2, first i am selecting pick qty as 1 and click on isert that record will be inserted to table2. so here i can isert that record two times , and if i try to insert 3rd time it should not allow, because del qty is only 2.

How can i achieve in case2 situation??? any helps

Thanks,

Venkat.