Enables the Pivotal Query Optimizer when running SQL queries. The default is off, Greenplum Database uses only the legacy query optimizer.

The Pivotal Query Optimizer co-exists with the legacy query optimizer. When the Pivotal Query Optimizer is enabled, Greenplum Database uses the Pivotal Query Optimizer to generate an execution plan for a query when possible. If the Pivotal Query Optimizer cannot be used, the legacy query optimizer is used.

The optimizer parameter can be set for a database system, an individual database, or a session or query.

For information about the legacy query optimizer and the Pivotal Query Optimizer, see "Querying Data" in the Greenplum Database Administrator Guide.