Schemaless Databases
Explore how to manage data schema changes in schemaless databases during application upgrades. Understand methods like all-version compatibility, migration routines, and the trickle then batch approach to minimize downtime and ensure smooth transitions. This lesson prepares you to handle evolving data structures effectively in deployed systems.
Old data, new application
If we’re using something other than a relational database, then we’re done. A schemaless database is only schemaless as far as the database engine cares. Our application is another story entirely. It expects certain structure in the documents, values, or graph nodes returned by our database. Will all the old documents work on the new version of our application? We mean all the old documents, way back to the very first customer record we ever created. Chances are your application has evolved over time, and old versions of those documents might not even be readable now. Harder still, our database may have a patchwork of documents, all created using different application versions, with some that have been loaded, updated, and stored at different points in time. Some of those documents will have turned into time bombs.
Reading old documents on new app versions
If we try to read one today, our application will raise an exception and fail to load it. Whatever ...