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2.3.16.31 Ndb::setEventBufferQueueEmptyEpoch()

Description.  Queuing of empty epochs is disabled by default. This method can be used to enable such queuing, in which case any new, empty epochs entering the event buffer following the method call are queued.

When queuing of empty epochs is enabled, nextEvent() associates an empty epoch to one and only one of the subscriptions (event operations) connected to the subscribing Ndb object. This means that there can be no more than one empty epoch per subscription, even though the user may have many subscriptions associated with the same Ndb object.

Signature. 

void setEventBufferQueueEmptyEpoch
  (
    bool queue_empty_epoch
  )

Parameters.  This method takes a single input parameter, a boolean. Invoking the method with true enables queuing of empty events; passing false to the method disables such queuing.

Return value.  None.

Note

setEventBufferQueueEmptyEpoch() has no associated getter method. This is intentional, and is due to the fact this setter applies to queuing new epochs, whereas the queue itself may still reflect the state of affairs that existed prior to invoking the setter. Thus, during a transition period, an empty epoch might be found in the queue even if queuing is turned off.

setEventBufferQueueEmptyEpoch() was added in NDB 7.4.11 and NDB 7.5.2.


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