Laser is a computing engine developed by Alibaba Cloud. Laser is transparent to you and can improve the performance of complex computing. Laser provides more than twice the performance of the open source Greenplum Database for 1 GB, 100 GB, 1 TB, or 10 TB of data.

Limits

  • We recommend that you use the ORCA optimizer.
  • Laser is supported only in AnalyticDB for PostgreSQL V6.0 and later.

Enable or disable Laser

To enable or disable Laser, you can set the global user configuration (GUC) parameter laser.enable to on or off. Laser can be enabled or disabled for sessions, databases, or instances. For sessions, Laser automatically enters its default status when the sessions are ended. For databases, Laser immediately takes effect. For instances, Laser takes effect after you restart the instances. This section describes how to view and modify the status of Laser.

  • Execute the following statement to view the status of Laser:
    SHOW laser.enable;

    Sample query result:

     laser.enable
    --------------
     on
    (1 row)
  • Execute the following statement to enable Laser for sessions:
    SET laser.enable = on;
  • Execute the following statement to disable Laser for sessions:
    SET laser.enable = off;
  • Execute the following statement to enable Laser for a database:
    ALTER DATABASE ${DBNAME} SET laser.enable = on;
  • Execute the following statement to disable Laser for a database:
    ALTER DATABASE ${DBNAME} SET laser.enable = off;
Note
  • You are not allowed to directly enable or disable Laser for instances. We recommend that you enable or disable Laser for sessions or databases. To enable or disable Laser for instances, Submit a ticket.
  • By default, Laser is disabled if the minor version is earlier than 6.3.4.0, and enabled if the minor version is 6.3.4.0 or later. For information about how to query and update the minor version, see Query the minor engine version and Upgrade the engine version.

Supported data types and operators

Laser supports the following data types:

  • INT2, INT4, and INT8
  • FLOAT4, FLOAT8, and NUMERIC
  • DATE, TIME, TIMETZ, TIMESTAMP, and TIMESTAMPTZ
  • VARCHAR, TEXT, and BPCHAR

Laser supports the following operators:

  • =, <, <=, >, >=, <>, !=, BETWEEN, IS NOT NULL, IS NULL, and LIKE
  • Logical operators: AND, OR, and NOT