ODAC

TOraQueue.AsyncNotification Property

Used to generate the OnMessage event each time when a new message is enqueued.

Class

TOraQueue

Syntax

property AsyncNotification: boolean default False;

Remarks

If the AsyncNotification propery is True, the TOraQueue component will generate the OnMessage event each time when a new message is enqueued.

When setting the AsyncNotification value to True, a message subscription is created in the queue. When setting the property value to False, the subscription is unregistered.

Active session is required to change the value of AsyncNotification, but TOraQueue doesn't need a session to get notifications. You can disconnect after setting the AsyncNotification value.

AsyncNotification property works only if OCI is initialized with the OCI_EVENTS flag. By default ODAC sets this flag if the OCI version is 9.0 or higher. If you need to use AsyncNotification with Oracle client 8.1, you should set the OCIEventsVersion variable from OraCall unit to 8100 in the initialization section of one of your program units.

AsyncNotification is not supported in Direct mode.

Note, the Oracle client version 8.1 has a bug when the NAMES.DEFAULT_DOMAIN parameter in the sqlnet.ora file is not working when the OCI_EVENTS flag is set.

See Also

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