The organization I currently work in deals with EHR systems where there's a desktop application and a web application. The desktop application records specific data of the patients via different sensors and then a Windows service written in C# syncs that data to a Cloud Server. So basically all the data in the local db ends up in our cloud db.

Ive Written the desktop application in such a way that it embeds an instance of IE in Windows Form application and that basically renders different HTML pages stored locally.

The only reason why we have a sync Mechanism is because some of our clients have unreliable internet connection.

The big problem we face is that everytime we have any change in schema of our local db, I have to write the sync code for that schema change and then add the same change on the cloud db too. and quite often we face many bugs in the sync service.

Moving on, Ive recently been quite fascinated by the concept of Progressive web apps and how it is being used by a lot of people nowadays.

I want to shift my desktop application to PWA such that instead of first storing data in local db I bypass the sync service and add that data directly to the cloud db. this would not only help us in removing the extra effort of working on the sync service but will also make the application fast as it will directly add entries to the cloud db.

I have done a lot of searching on the internet but I cant seem to understand how the PWA in our case will manage the data in case our client has unreliable connection or is offline all together. how will the caching mechanism work when our application heavily depends on the Database?

Id really appreciate any workaround in this scenario..