The SQS can be used to offload requests from another service onto the queue. For example an application with several services stores its state in a relational database. If one of the services changes state, then all the others would need to check the database for changes. This would mean the services would constantly scan the database and look for changes. Instead of doing this, the service that changes state can inform one or multiple services of the changes via the message queue. The message can contain the exact index that has changed in the database, and the receiver now only needs to look at that index in the database to determine how the state has changed.