Determining The Timeout That Is In Effect

Determining the Timeout that is In Effect

The effective idle timeout value is determined whenever a user API call leaves the engine, checking first at connection level and then at database level.A connection-level timeout can override the value of a database-level setting, as long as the period of time for the connection-level setting is no longer than any non-zero timeout that is applicable at database level.

Important

Take note of the difference between the time units at each level.At database level, in the configuration files, the unit for SessionTimeout is minutes.In SQL, the default unit is minutes but can also be expressed in hours or seconds explicitly.At the API level, the unit is seconds.

Absolute precision is not guaranteed in any case, especially when the system load is high, but timeouts are guaranteed not to expire earlier than the moment specified.

`SET STATEMENT TIMEOUT`

Sets the statement timeout for a connection

Syntax

SET STATEMENT TIMEOUT value [<time-unit>]

<time-unit> ::= SECOND | MILLISECOND | MINUTE | HOUR

Table 1. `SET STATEMENT TIMEOUT` Statement Parameters
Parameter	Description
value	The timeout duration expressed in time-unit.A value of `0` defers to statement timeout configured for the database.
time-unit	Time unit of the timeout.Defaults to `SECOND`.

The SET STATEMENT TIMEOUT sets a statement timeout at connection level and takes effect immediately.The statement can run outside transaction control (without an active transaction).

Setting a value larger than configured for the database is allowed, but is effectively ignored, see also [fblangref50-management-stmnt-timeout-effective].

The current statement timeout set for the session can be retrieved through RDB$GET_CONTEXT, namespace SYSTEM and variable STATEMENT_TIMEOUT.Information is also available from MON$ATTACHMENTS:

MON$STATEMENT_TIMEOUT: Connection-level statement timeout in milliseconds;0 if timeout is not set.

In MON$STATEMENTS:

MON$STATEMENT_TIMEOUT: Statement-level statement timeout in milliseconds;0 if timeout is not set.
MON$STATEMENT_TIMER: Timeout timer expiration time;contains NULL if an idle timeout was not set, or if a timer is not running.

Both RDB$GET_CONTEXT('SYSTEM', 'STATEMENT_TIMEOUT') and MON$ATTACHMENTS.MON$STATEMENT_TIMEOUT report the statement timeout configured for the connection, and MON$STATEMENTS.MON$STATEMENT_TIMEOUT for the statement;they do not report the effective statement timeout.

The statement timeout is reset when [fblangref50-management-session-reset-alter] is executed.