When you configure pushdown optimization, the Integration Service tries to push each transformation to the database. The following criteria affects whether the Integration Service can push the transformation to the database:

• Type of transformation.
• Location of the transformation in the mapping.
• Mapping and session configuration for the transformation.
• The expressions contained in the transformation.

The criteria might also affect the type of pushdown optimization that the Integration Service can perform and the type of database to which the transformation can be pushed. To use full pushdown optimization, the source and target databases must be in the same relational database management system. This particular example demonstrates the ability to use the partial pushdown functionality when source are target are on different systems. Source-side pushdown optimization: The Integration Service pushes as much transformation logic as possible to the source database.Target-side pushdown optimization: The Integration Service pushes as much transformation logic as possible to the target database.