How to Scale Applications using CQRS

Design your cloud application for high performance, better security, and scalability using Command and Query Responsibility Segregation (CQRS) design pattern.

Your Inventory application suffers from performance issues while updating the stock and also when the e-commerce site queries the item stock to check the item availability. The situation becomes terrible during peak shopping events.

The performance issue of updating and querying the same data entity can be resolved using the CQRS design pattern, where CQRS stands for Command and Query Responsibility Segregation.

Command and Query Responsibility Segregation(CQRS) separates the command from the query part of the system.

Command refers to the data mutation actions like inserts, updates, and deletes. Query reads the data to display it for the users.

Command and Query Responsibilities are Segregated(image by author)

The separation of the commands from queries help

• Implement complex validation and business logic.
• Allows the selection of the best database for the job, like an RDBMS for command and a NoSQL designed for effective reads.