When you use an outer join, the Designer generates a LEFT OUTER JOIN statement in the ABAP program. You can use more than one outer join in the ABAP program flow. However, the tables you can join using outer join depends on how you join other tables in the program flow.

For example, you have three tables, KONH, KONP, and KONM in the ABAP program flow. You join KONP with KONH using an outer join. When you select KONM in the program flow, you cannot join KONM with KONP using an outer join. If you join KONM with KONP using an outer join, the Designer returns an error message when you generate the ABAP program.

In this example, you can only choose KONH because you already joined KONP with KONH using an outer join. When you join KONP and KONH with an outer join, the ABAP program selects rows that exist in both KONP and KONH, and it discards rows that only exist in KONP.

The same outer join concept applies to an ABAP program with any number of objects.