Cloudera Enterprise 6.3.x | Other versions

QUERY_TIMEOUT_S Query Option (CDH 5.2 or higher only)

Sets the idle query timeout value for the session, in seconds. Queries that sit idle for longer than the timeout value are automatically cancelled. If the system administrator specified the --idle_query_timeout startup option, QUERY_TIMEOUT_S must be smaller than or equal to the --idle_query_timeout value.

  Note:

The timeout clock for queries and sessions only starts ticking when the query or session is idle.

For queries, this means the query has results ready but is waiting for a client to fetch the data. A query can run for an arbitrary time without triggering a timeout, because the query is computing results rather than sitting idle waiting for the results to be fetched. The timeout period is intended to prevent unclosed queries from consuming resources and taking up slots in the admission count of running queries, potentially preventing other queries from starting.

For sessions, this means that no query has been submitted for some period of time.

Syntax:

SET QUERY_TIMEOUT_S=seconds;

Type: numeric

Default: 0 (no timeout if --idle_query_timeout not in effect; otherwise, use --idle_query_timeout value)

Added in: CDH 5.2.0 / Impala 2.0.0

Related information:

Setting Timeout Periods for Daemons, Queries, and Sessions

Page generated August 29, 2019.