This wiki gives a quick example on how one listbox can be filled with data from two data sources joining arrays and looping through them.
1. Add the data sources to DS application. In this example we are going to use DS_18_AOAZ and DS_18_AOAZ_A to fill the list box LISTBOX_AOAZ.
2. Now select the on-startup Event of your page-book and fill in the script code below. Replace “0FISCYEAR” and “KH_GPKI02__F1” with the Dimension (technical name) you want to be filled in the Drop down component. The script joins two arrays of different data sources and checks whether an element is already in the list or not.