When you use an ODBC connection in a mapping to read data from a source, transform the data, and write the data to a target, you can configure SQL ELT optimization to push the transformation logic to the source or target database system. If the source and target databases are the same, you can configure full SQL ELT optimization for improved performance.
When the Secure Agent applies SQL ELT optimization, it pushes transformation logic to the 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. The amount of transformation logic that the Secure Agent pushes to the database depends on the database, the transformation logic, and the mapping configuration. The Secure Agent processes all transformation logic that it cannot push to a database.
SQL ELT optimization improves mapping performance because the database processes the transformation logic faster than the Secure Agent. The amount of data that the Secure Agent needs to read from the database is reduced. When you push the transformation logic to the database, ensure that the database has enough resources to process the queries faster. Otherwise, there could be a performance degradation.
You cannot configure SQL ELT optimization for a mapping in advanced mode.