rxdb | A fast , offline-first , reactive Database for JavaScript | Database library

I just changed my rxdb schema version from 0 to 1 in order to add a deletedAt attribute. I added a migration strategy for going from ver 0 to 1.

Now I'm getting this error: "migration of document failed final document does not match final schema". The final doc is in screenshot below:

I thought maybe I had to add the _rev field; adding _rev to schema didn't remove the error, so I've taken it back out. Ditto with a deleted field (complains I can't add it as a top-level attribute). So I am at a loss as to why else the final object differs from the expected schema?

I'm planning on using rxdb + hasura/postgresql in the backend. I'm reading this rxdb page for example, which off the bat requires sync-able entities to have a deleted flag.

• Is there ANY point at which I can finally hard-delete these entities? What conditions would have to be met - eg could I simply use "older than X months" and then force my app to only ever displays data for less than X months?
• Is such a hard-delete, if possible, best carried out directly in the central db, since it will be the source of truth? Would there be any repercussions client-side that I'm not foreseeing/understanding?

I foresee the number of deleted's growing rapidly in my app and i don't want to have to store all this extra data forever.

Q2 (bonus / just curious)

• What is the (algorithmic) basis for needing a 'deleted' flag? Is it that it's just faster to check a flag rather than to check for the omission of an object from, say, a very large list. I apologize if it's kind of a stupid question :(

I'm developing an app with Electron, but I have a problem to exchange a variable between several files.

In my main.js, I create an RxDB database that is used for my entire project. At this level, I also create handlers allowing the communication between the main process and the render process via IPC. These handlers call various Classes that perform various processes including database insertions, modifications, etc.

In my opinion, I haven't found an efficient way to transmit my variable containing my database to my classes.

Ideally, I should be able to call this database variable (declared in main.js) at any time from any class. I can't use the IPC system because my returned variable must not be a JSON but absolutely an RxDatabase object.

Here is a very simplified diagram of my main process:

Currently, to share my database variable to my classes:

• I declare the variable in main.js
• I transmit the variable in the handlers
• I transmit the variable to my classes in a static variable class

Although ugly, this system works. But I think there is a more correct way to do it. Also, it becomes difficult to preserve this variable when a class calls one or more instances of external classes.

Thanks.