Source Qualifier transformations determine the rows or records that the PowerCenter Integration Service reads from the source when you run a session.
When you add a relational or a flat file source definition to a mapping, you need to connect it to a Source Qualifier transformation. The type of source qualifier transformation depends on the source definition type:
For relational source definitions, use a Source Qualifier transformation.
For nonrelational source definitions, use an Application Multi-Group Source Qualifier transformation.