This article provides information about how to make a newer version of extension upgrade available on tenants. The first phase of the process is to develop the extension for upgrading. In this phase, you add code to upgrade data from the previous extension version. Once you have the upgrade code in place, you can publish and synchronize the new version, and the run the data upgrade.
When you develop a new extension version, you must consider the data from the previous version. Determine the modifications that must be made to the data to make it compatible with the current version. For example, maybe the new version adds a new field that needs default values set for existing records. Or, the new version adds new tables that must be linked to existing records. To address this type of data handling, you must write upgrade code for the extension version. If there are no data changes between the extension versions, you don't need to write upgrade code. All data that isn't modified by upgrade code will automatically be available when the process completes.