All great questions, thanks!
I’m a bit worried about lock-in. Will the new database be open source and allow for SQL queries? What’s the reason Logseq couldn’t go with a solution like SQLite?
Our forked Datascript is at GitHub - logseq/datascript: Immutable database and Datalog query engine for Clojure, ClojureScript and JS, We added persistent storage support and other features, currently, the underlying data will be stored to SQLite through GitHub - sqlite/sqlite-wasm: SQLite Wasm conveniently wrapped as an ES Module..
Also, regarding sync, will that be one of the paywalled features that “rely on [Logseq] servers”? I’m wondering if there will be options for third-party syncing, possibly similar to how Joplin implements it (offering people the ability to host their own notes or pay to use Joplin Cloud). Or will people looking for free syncing have to stick with the markdown version?
The whole db can be exported as a SQLite file, which means you can still use third-party tools to sync. We have no plan to design a sync protocol so that the community can bring in other implementations because merging conflicts from other clients is very complex, but this could be changed in the future when RTC is stable and we have more resources to design a protocol.