Transformation Pushdown Logic
The Data Integration Service uses pushdown optimization to push transformation logic to source databases. The amount of transformation logic that the Data Integration Service pushes to the source database depends on the database, the transformation logic, and the mapping configuration. The Data Integration Service processes all transformation logic that it cannot push to a database.
The Data Integration Service can push the following transformation logic to the source database:
- •Aggregator
- •Expression
- •Filter
- •Joiner
- •Lookup
- •Sorter
- •Union
The Data Integration Service cannot push transformation logic to a source in the following circumstances:
- •The source contains a column with a binary data type.
- •The source is a customized data object that contains a filter condition or user-defined join for Expression or Joiner transformation logic.
- •The sources are on different database management systems or use different connections for Joiner or Union transformation logic.
- •The lookup match policy is not set to "Return All Rows."
The Data Integration Service processes mapping logic that it cannot push to the source.