Overview of GPORCA

GPORCA extends the planning and optimization capabilities of the Postgres Planner.GPORCA is extensible and achieves better optimization in multi-core architecture environments. LightDB-A Database uses GPORCA by default to generate an execution plan for a query when possible.

GPORCA also enhances LightDB-A Database query performance tuning in the following areas:

  • Queries against partitioned tables
  • Queries that contain a common table expression (CTE)
  • Queries that contain subqueries

In LightDB-A Database, GPORCA co-exists with the Postgres Planner. By default, LightDB-A Database uses GPORCA. If GPORCA cannot be used, then the Postgres Planner is used.

The following figure shows how GPORCA fits into the query planning architecture.

Query planning architecture with GPORCA

Note All Postgres Planner server configuration parameters are ignored by GPORCA. However, if LightDB-A Database falls back to the Postgres Planner, the planner server configuration parameters will impact the query plan generation. For a list of Postgres Planner server configuration parameters, see Query Tuning Parameters.

Parent topic: About GPORCA