This is a very quick post just to help on clearing doubts related on a new flag that Microsoft has introduced on the Extension Management page in Dynamics 365 Business Central starting from the 16.5 update (but announced for general availability for version 17).
If you try to uninstall an extension form that page, now you have the new Delete Extension Data option:
This option is false as default (so, when you uninstall an extension all its data and schema are preserved).
If you turn this option on, what does it do? It deletes the extension’s data or also the schema? I see doubts on this.
This option permits you to delete all the extension’s data (data on tables, table extensions, isolated storage) and also the database schema of the extension (so, it performs a database modifications). This is a SaaS analogue way of performing a Sync-NavApp -Mode Clean with Powershell in the on-premise world, so use it carefully because your extension’s data will be lost forever.
Is it useful?
In my opinion absolutely yes. It’s always a better way to install extensions in an automated way (DevOps or Automation API) but having a manual way to completely remove an extension from the system (data + schema) was a need from a long time I think. I’ve suggested in the past to rename the flag with something more intuitive as “Delete Extension Data and Schema” but that’s another story…