What is publisher subscriber in messaging?
Publish/subscribe messaging, or pub/sub messaging, is a form of asynchronous service-to-service communication used in serverless and microservices architectures. In a pub/sub model, any message published to a topic is immediately received by all of the subscribers to the topic.
What design pattern best describes the publish subscribe messaging?
The Publish/Subscribe pattern, also known as pub/sub, is an architectural design pattern that provides a framework for exchanging messages between publishers and subscribers. This pattern involves the publisher and the subscriber relying on a message broker that relays messages from the publisher to the subscribers.
Which communication model has a queue between publisher and subscriber?
Publish–subscribe is a sibling of the message queue paradigm, and is typically one part of a larger message-oriented middleware system. Most messaging systems support both the pub/sub and message queue models in their API; e.g., Java Message Service (JMS).
How a publish and subscribe system works?
Publish/Subscribe (Pub/Sub) messaging provides instant event notifications for these distributed applications. The Publish Subscribe model allows messages to be broadcast to different parts of a system asynchronously. To broadcast a message, a component called a publisher simply pushes a message to the topic.
How does replication work in a publishing model?
A Subscriber can receive data from multiple Publishers and publications. Depending on the type of replication chosen, the Subscriber can also pass data changes back to the Publisher or republish the data to other Subscribers. An article identifies a database object that is included in a publication.
Is it possible to have many publishers and only one subscriber?
2 Answers 2. Yes it is possible to have many publishers and only one subscriber. You can also have one publisher and many subscribers. So in your case you will be able to publish from City1 and City2 and subscribe only City1 on those publishers. You can use this link to have an overview of the replication engine and how to setup it.
How is a publisher associated with a distributor?
Distributor. Each Publisher is associated with a single database (known as a distribution database) at the Distributor. The distribution database stores replication status data, metadata about the publication, and, in some cases, acts as a queue for data moving from the Publisher to the Subscribers.
How does replication database work in SQL Server?
The distribution database stores replication status data, metadata about the publication, and, in some cases, acts as a queue for data moving from the Publisher to the Subscribers. In many cases, a single database server instance acts as both the Publisher and the Distributor. This is known as a local Distributor.