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BLOCKING OptionLocate this document in the navigation structure

Controls the behavior in response to locking conflicts. BLOCKING is not supported on secondary nodes of a multiplex.

Allowed Values

ON, OFF

Default

OFF

Scope

Option can be set at the database (PUBLIC) or user level. At the database level, the value becomes the default for any new user, but has no impact on existing users. At the user level, overrides the PUBLIC value for that user only. No system privilege is required to set option for self. System privilege is required to set at database level or at user level for any user other than self.

Requires the SET ANY PUBLIC OPTION system privilege to set this option. Can be set temporary for an individual connection or for the PUBLIC role. Takes effect immediately.

Remarks

When BLOCKING is off, a transaction receives an error when it attempts a write operation and is blocked by the read lock of another transaction.

When BLOCKING is on, any transaction attempting to obtain a lock that conflicts with an existing lock held by another transaction waits until every conflicting lock is released or until the blocking_timeout is reached. If the lock is not released within blocking_timeout milliseconds, then an error is returned for the waiting transaction.