Publish and Subscribe Interview Questions?

1.            Where is document routed when broker is not available?

·         OUTBOUND document store.

2.            Name different storage type of publishable document?

·         Guaranteed and volatile.

3.            What is difference between storage type guaranteed and volatile?

·          This storage type helps Broker, how to store a doc. Guaranteed: It is stored on disk and also on memory. Volatile: The broker stores the document in memory only.

4.            How do broker routs the document to subscriber?

·         If the document was published as broadcast, the broker identifies subscriber and places a copy of the doc in the client queue for each subscriber. If the doc was delivered, the broker places the document in the queue for client specified in the delivery request.

5.            Name the element in webMethods that actually supervises the document transfer between IS and Broker?

·         Dispatcher.

6.            What happen if no subscriber type is specified in document?

·         The Broker returns the acknowledgement (ACK) to the publisher and then discard the document or in case of dead letter subscription, the broker deposit the doc in queue containing dead letter subscriber.

7.     During implementation of “Exactly Once” properties in trigger, what are the three elements helps in resolving document status?

·          1. Redelivery count; 2. Document History DB; 3. Document resolver service.

8.            What is the three status of duplicate detection in trigger for document status?

·           NEW, DUPLICATE, IN_DOUBT