Is there a reason you want the original script in a datatable? You could save your script as a .jsl file and have that open the new data and add any new columns/scripts to it. You can also have the script run automatically and close itself after the table is created.
If there is another reason to run it from a table, you can concatenate or join the new data back to your original table.
dtCurrent = Current Data Table();
dtNew = Open( .. some database query ..);
dtCurrent << Concatenate( dtNew, Append to first table );
dtNew << Close Window;