Select Distinct is a command that returns rows with a distinct set of key values. Use Select Distinct with open SQL, exec SQL, and ABAP join syntax. When you use open SQL, the Designer generates a select distinct statement for each source definition you configure with the Select Distinct option.

You might use this option when you only want to return records associated with particular key values. Select Distinct improves performance by filtering out unnecessary data early in the data flow.

If you join multiple sources in a single Application Source Qualifier configured for exec SQL and ABAP join syntax, and you want to use select distinct, choose Select Distinct for each source connected to the Application Source Qualifier. The Designer generates a Select Distinct statement with exec SQL only when you configure all of the source definitions with the Select Distinct option.

The Select Distinct option is not available for hierarchy and IDoc definitions.