cr-sqlite VS wa-sqlite

I'm a happy user of https://github.com/vlcn-io/cr-sqlite/

If you're interested in this, here are some related projects that all take slightly different approaches:

- LiteSync directly competes with Marmot and supports DDL sync, but is closed source commercial (similar to SQLite EE): https://litesync.io

- dqlite is Canonical's distributed SQLite that depends on c-raft and kernel-level async I/O: https://dqlite.io

- cr-sqlite is a Rust-based loadable extension that adds CRDT changeset generation and reconciliation to SQLite: https://github.com/vlcn-io/cr-sqlite

Slightly related but not really (no multi writer, no C-level SQLite API or other restrictions):

- comdb2 (Bloombergs multi-homed RDMS using SQLite as the frontend)

- rqlite: RDMS with HTTP API and SQLite as the storage engine, used for replication and strong consistency (does not scale writes)

- litestream/LiteFS: disaster recovery replication

- liteserver: active read-only replication (predecessor of LiteSync)

Theory is great, but how can we apply this in practice? Instead of starting from 0, and writing a CRDT, let's try and leverage an existing project to do the heavy lifting. My choice is crSQLITE, an extension for SQLite to support CRDT merging of databases. Under the hood, the extension creates tables to track changes and allow inserting into an event log for merging states of separated peers.

Also https://github.com/vlcn-io/cr-sqlite/ which is SQLite + CRDTs

Runs/syncs to the browser too which is just lovely.

If you need multiple writers and can handle eventual correctness, you should really be using cr-sqlite[1]. It'll allow you to have any number of workers/clients that can write locally within the same process (so no network overhead) but still guarantee converge to the same state.

[1] https://github.com/vlcn-io/cr-sqlite

I am fully on the offline-first bandwagon after starting to use cr-sqlite (https://vlcn.io), which works similar to ElectricSQL.

I thought the bundle size of wasm-sqlite would be prohibitive, but it's surprisingly quick to download and boot. Reducing network reliance solves so many problems and corner-cases in my web app. Having access to local data makes everything very snappy too - the user experience is much better. Even if the user's offline data is wiped by the browser (offline storage limits are a bit of a minefield), it is straightforward to get all synced changes back from the server.

I didn't know that. Especially the first approach sounds interesting to me, because as far as I know the transactions of Yjs seem to be a problem on heavily changing documents. https://github.com/vlcn-io/cr-sqlite#approach-1-history-free... Thanks!

I wonder how this compares to https://vlcn.io?

The short ask: Anyone know of any projects that bring incremental view maintenance to SQLite?

The why:

Applications are usually read heavy. It is a sad state of affairs that, for these kinds of apps, we don't put more work on the write path to allow reads to benefit.

Would the whole No-SQL movement ever even have been a thing if relational databases had great support for materialized views that updated incrementally? I'd like to think not.

And more context:

I'm working to push the state of "functional relational programming" [1], [2] further forward. Materialized views with incremental updates are key to this. Bringing them to SQLite so they can be leveraged one the frontend would solve this whole quagmire of "state management libraries." I've been solving the data-sync problem in SQLite (https://vlcn.io/) and this piece is one of the next logical steps.

If nobody knows of an existing solution, would love to collaborate with someone on creating it.

[1] - https://github.com/papers-we-love/papers-we-love/blob/main/design/out-of-the-tar-pit.pdf

The word on the street is that https://github.com/rhashimoto/wa-sqlite is nearly production ready, closing in on the neat 1.0.0 release, with its IDBBatchAtomic engine highly recommended at https://www.powersync.com/blog/sqlite-persistence-on-the-web. You can try out the benchmark https://rhashimoto.github.io/wa-sqlite/demo/benchmarks.html.

And the other contestant is Dexie, stable https://dexie.org/.

If you were to branch into a new venture today, which one would you pick? And why?

It seems indeed very nice, the examples are clear and everything works from async. I tried with Deno, and now experimenting with my own VFS.

It does seem to suffer from maintainer problems too though, and I don't blame Roy Hashimoto for that. I wouldn't want to maintain such an obvious wrapper when it should be a task for SQLite's team to upstream the changes.

Roy Hashimoto doesn't want to maintain it as an NPM package for instance, as it is just an experiment: https://github.com/rhashimoto/wa-sqlite/issues/12

"Low traffic is a happy place - I don't have any motivation to mess with that."

This is the WASM blob and it's 1.1 MB uncompressed. https://github.com/rhashimoto/wa-sqlite/blob/master/dist/wa-.... No issues - it's cached by cloudflare.

We're using IndexedDB. Here's a writeup on alternatives https://github.com/rhashimoto/wa-sqlite/issues/85 and a benchmark https://rhashimoto.github.io/wa-sqlite/demo/benchmarks.html

I have a genuine appreciation for how Linear has built this. We have had to build something similar for our note taking application (Reflect). It is very tricky to do and I wish there was more research on this.

In my opinion, what we need is:

1) A client-side performant SQLite database that supports live queries. I.e. you can automatically re-render the page when the queries change. That way your database can drive the UI and be the source of truth in regards to what's displayed on the screen.

2) A separate realtime syncing protocol that syncs database state to client state.

And ideally this is all open source, and that these two endeavors are not coupled tightly.

[1] Wa-sqlite is the best (imo) client-side db - better than than the official Sqlite WASM build (for now) because it had a indexeddb fallback for browsers that aren't the cutting edge Chrome.

[2] cr-sqlite is an interesting project using CRDTs to sync state around. However I still believe that for many production use-cases you want a ultimate server source of truth.

[3] Replicache is still the best closed source solution I know of.

[1] - https://github.com/rhashimoto/wa-sqlite

[2] https://github.com/rhashimoto/wa-sqlite/discussions/63