Netezza Connector > Netezza ODBC pushdown optimization > Pushdown optimization overview
  

Pushdown optimization overview

When you read data from a Netezza source, transform the data, and write the data to a target, you can configure pushdown optimization to push the transformation logic to the source or target database system.
You can configure pushdown optimization when you use a Netezza ODBC connection that uses Netezza ODBC drivers in the mapping.
If the source and target databases are the same, you can configure full pushdown optimization for improved performance.
When the Secure Agent applies pushdown optimization, it pushes transformation logic to a database. The Secure Agent translates the transformation logic into SQL queries and sends the SQL queries to the database. The database runs the SQL queries to process the transformations.
Pushdown optimization improves mapping performance when the database can process the transformation logic faster than the Secure Agent. The Secure Agent also reads less data from the database.
The amount of transformation logic that the Secure Agent pushes to the database depends on the database, the transformation logic, and the mapping task. The Secure Agent processes all transformation logic that it cannot push to a database.
When you configure pushdown optimization for the mapping, the Secure Agent analyzes the optimized mapping from the source to the target or until it reaches a downstream transformation that it cannot push to the source database. The Secure Agent generates and executes a SELECT statement for each source that has transformation logic pushed down. Then, it reads the results of this SQL query and processes the remaining transformations in the mapping.

Full pushdown

The ODBC connection supports Source pushdown optimization when you use the Netezza ODBC driver in a mapping.
You can configure full pushdown optimization only when the source and target are in the same database.
When the Secure Agent applies full pushdown optimization, it pushes all the transformation logic in the mapping to the target database. You can configure full pushdown in the Pushdown Optimization section on the Schedule tab of the mapping task.
Full pushdown optimization is ideal when the source and target are in the same connections. For example, if a mapping contains a Netezza source and a Netezza target, configure full pushdown optimization to push all the transformation logic for processing from a Netezza source database to a Netezza target database.

Source pushdown

The ODBC connection supports Source pushdown optimization when you use the Netezza ODBC driver in a mapping.
When the Secure Agent applies source pushdown, it analyzes the mapping from source to target or until it reaches a downstream transformation it cannot push to the source database.
The Secure Agent generates and executes a SELECT statement based on the transformation logic for each transformation it can push to the database. Then, it reads the results of this SQL query and processes the remaining transformations.
You can configure a mapping to use source pushdown if the source and target reside in different databases. For example, if a mapping contains a Netezza source and a Netezza target, you can configure source pushdown to push some transformation logic for processing to the Netezza source.
You can configure source pushdown in the Pushdown Optimization section on the Schedule tab of the mapping task.