Next the Source table mapping dialog appears. This dialog is used to join source tables, add where clauses and specify group by clauses.

To join two tables, start by selecting the two tables in the left hand box and then clicking one of the join buttons. The columns for the two tables then appear at the bottom of the dialog and one column is selected from each drop down list to effect the join between the selected tables. In the example above the load_order_header and load_order_line tables are joined by the column order_no. For multiple column joins, repeat the join process.