I would like to display values in a second list box based on a value in the first list box. For example suppose that list box A contains the values

a b
c d
e f
etc

from table data1. Then if I click on a line in list box A I want list box B to show the files

h i j
k l m
n o p
etc

from table data2 where the triplets are based on the values a, b, c etc (i,e field data2.field = data1.field where field is a, b, c, etc. Is this possible if so.