I'm looking for a good way to edit invoice rows.

First I tried to use a grid based on a table with linkmaster,childorder,relationalexpression properties.
For some strange reason, grid displays all rows, not current invoice.

Second I created a parametrized local view.
However, invoice row table data does not have primary or candidate key so it is not possible to update it using local view !?

Which is the best way to edit child records in one to many
relationship?