Check if the value of a field in internal table exists in the database

Hello everyone,

I have a requirement where i need to check if the value of the field of a record in the internal table exist in the F4 help of the corresponding field in the database table.

For example : In transaction VA01 when we give the order quantity other than the ones specified in the f4 help an error message is raised as it is not present in the TVAK value table.Now if my internal table has an invalid entry then i need to move those entries to another internal table(itab1) and if the entries are valid i should move those entries into another internal table(itab2).

Please help me out in Validating all the fields of the internal field.Any suggestions in this regard would be very helpful for me 😊