CQRS

  • Command & Query Responsibility Segregation:
  • i.e Segregate query responsibility which is nothing but read operation and command responsibility which is write operation.

  • CQRS suggests us to segregate read and write operation to different microservices rather than mix up in a single service.

  • Why do I duplicate the service to just serve different responsibility ??

  • For an example, we are using Flipkart/Amazon ecommerce application, so there will be many read /search requests than write / add to cart requests.
  • We can't scale the application independently for read and write request.
  • Writing Complex Queries.x
  • Additional Security

Query /GET - Fetch Products

Command /POST - Create Products /PUT - Update Products /DELETE - Delete Products

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  • In order to sync both the micro-services to avoid data inconsistency we can use any messaging system like kafka, RabbitMQ or Redis PubSub