What does the session consistency model ensure?

The session consistency model ensures that changes are seen in the order they are made for the same application. This means that within a single session, when an application writes data and subsequently reads that data, it will always read the most recent write. If a user or application submits multiple changes, they will see those modifications in the order they were made throughout their session. This consistency model addresses the requirement for having confidence in the state of the data, as it provides a predictable view of the data changes.

In scenarios where multiple users or applications are interacting with the same data, session consistency can be particularly beneficial. It allows applications to process information without encountering conflicts or confusion about the order of updates, which is especially important for user experience in applications that rely on real-time data interaction.

In contrast, other consistency models like eventual consistency may allow data to be viewed out of order, or not reflect changes immediately. The session consistency model specifically prioritizes the user's experience within a single session, ensuring that the actions taken by that application are consistently visible and presented in the exact order they occurred.