Changing runtime priority of a running query

CHANGE_CURRENT_STATEMENT_RUNTIME_PRIORITY lets you to change a query's runtime priority.

CHANGE_CURRENT_STATEMENT_RUNTIME_PRIORITY lets you to change a query's runtime priority. You can change the runtime priority of a query that is already executing.

This function takes two arguments:

  • The query's transaction ID, obtained from the system table SESSIONS

  • The desired priority, one of the following string values: HIGH, MEDIUM, or LOW

Restrictions

Superusers can change the runtime priority of any query to any priority level. The following restrictions apply to other users:

  • They can only change the runtime priority of their own queries.

  • They cannot raise the runtime priority of a query to a level higher than that of the resource pools.

Procedure

Changing a query's runtime priority is a two-step procedure:

  1. Get the query's transaction ID by querying the system table SESSIONS. For example, the following statement returns information about all running queries:

    => SELECT transaction_id, runtime_priority, transaction_description from SESSIONS;

  2. Run CHANGE_CURRENT_STATEMENT_RUNTIME_PRIORITY, specifying the query's transaction ID and desired runtime priority:

    => SELECT CHANGE_CURRENT_STATEMENT_RUNTIME_PRIORITY(45035996273705748, 'low')