About GPORCA

In HAWQ, you can use GPORCA or the legacy query optimizer.

Note: To use the GPORCA query optimizer, you must be running a version of HAWQ built with GPORCA, and GPORCA must be enabled in your HAWQ deployment.

These sections describe GPORCA functionality and usage:

  • Overview of GPORCA

    GPORCA extends the planning and optimization capabilities of the HAWQ legacy optimizer.

  • GPORCA Features and Enhancements

    GPORCA includes enhancements for specific types of queries and operations:

  • Enabling GPORCA

    Precompiled versions of HAWQ that include the GPORCA query optimizer enable it by default, no additional configuration is required. To use the GPORCA query optimizer in a HAWQ built from source, your build must include GPORCA. You must also enable specific HAWQ server configuration parameters at or after install time:

  • Considerations when Using GPORCA

    To execute queries optimally with GPORCA, consider certain criteria for the query.

  • Determining The Query Optimizer In Use

    When GPORCA is enabled, you can determine if HAWQ is using GPORCA or is falling back to the legacy query optimizer.

  • Changed Behavior with GPORCA

    When GPORCA is enabled, HAWQ’s behavior changes. This topic describes these changes.

  • GPORCA Limitations

    There are limitations in HAWQ when GPORCA is enabled. GPORCA and the legacy query optimizer currently coexist in HAWQ because GPORCA does not support all HAWQ features.