mvsqlite VS libsql

I’ve been using FDB for toy projects for a while. It’s truly rock solid. That being said, I wish there were more layers.

Ideally someone could implement the firestore or dynamodb api on top.

https://github.com/losfair/mvsqlite

For the rough plan, it's Cloud Backed SQLite meets FoundationDB.

- Oh, and if you're wondering about backup to S3, they have that too: https://github.com/libsql/bottomless

- Uh, sqld can integrated with this https://github.com/losfair/mvsqlite, so now your SQLite is backed by FoundationDB!?

- Meanwhile Litestream exists https://github.com/benbjohnson/litestream/

Shameless plug of my [mvSQLite](https://github.com/losfair/mvsqlite) project here! It's basically another distributed SQLite, but with support for everything expected from a proper distributed database: synchronous replication, strictly serializable transactions, + scalable reads and writes w/ multiple concurrent writers.

This project looks really exciting!

I'm working on mvsqlite [1], a distributed SQLite based on FoundationDB. When doing the VFS integration I have always wanted to patch SQLite itself, but didn't because of uncertainty around correctness of the patched version...

A few features on my wishlist:

1. Asynchronous I/O. mvsqlite is currently doing its own prefetch prediction that is not very accurate. I assume higher layers in SQLite have more information that can help with better prediction.

2. Custom page allocator. SQLite internally uses a linked list to manage database pages - this causes contention on any two transactions that both allocate or free pages.

3. Random ROWID, without the `max(int64)` row trick. Sequentially increasing ROWIDs is a primary source of contention, and causes significant INSERT slowdown in my benchmark [2].

[1] https://github.com/losfair/mvsqlite

[2] https://univalence.me/posts/mvsqlite-bench-20220930

That DynamoDB VFS looks cool! I agree that the VFS api makes one think about plenty of crazy ideas. Someone is working on a VFS based on Foundation DB[0] that looks very promising. It was recently discussed here[1]

[0]: https://github.com/losfair/mvsqlite

[1]: https://news.ycombinator.com/item?id=32269287

Astro DB is powered by LibSQL, an open source fork of SQLite that was created by Turso. You can use Astro DB's drop-in database to build features like blogs, comment functionality, forums, feedback systems, and user authentication.

sqlite already had an active community fork started by Turso called libsql. They are fixing longstanding API gaps the upstream team isn’t interested in supporting. For example, they added a native write-ahead log API, so you can plug directly into the WAL for streaming replication. This is possible-ish with upstream sqlite + LiteFs but litefs has to implement a whole FUSE file system and can’t run on Mac for that reason.

It’s more risky to run libsql because new features mean new bugs, but it seems worth it to me.

Libsql: https://github.com/tursodatabase/libsql

A bit of a tangent but for those who’d like to use SQLite for a backend, running it as a separate daemon could be an interesting choice, which would also remove there need of Cgo for the build and maybe make things like separate background job processes easier to accomplish. See [1], [2].

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1: https://github.com/tursodatabase/libsql/tree/main/libsql-ser...

2: https://news.ycombinator.com/item?id=38602175

https://www.sqlite.org/copyright.html

To summarize, instead of using one of the OSS licenses, the copyright holders simply declare the source to be in the public domain. In order to preserve that status they don't accept patches unless you submit some signed document that you agree with that.

To make things more complicated, they also use their a relatively niche version management system instead of git. Which would complicate making contributions (if they accepted them).

There's a popular fork that fixes all of these issues: https://github.com/libsql/libsql It is MIT licensed, on Github, and open for contributions.

Kind of a weird legal situation for a popular project like this that so many people depend on to have. Not judging; but it is odd. Seems like a lot of wasted efforts between users, would be contributors, and the people that forked this thing to address all that.

You could try making feature requests for https://github.com/libsql/libsql , which is a community fork of SQLite that aims to speed-up the development of long-wanted features.

For a comprehensive view, check out the issues list for libSQL core and sqld. But mostly, I want libSQL to be a home for all builders who believe there is room to take a lean, mean, and SQLite-compatible embedded database to new heights. I’d love to see your contribution!

Wild stuff

- Fork of SQLite with new features https://github.com/libsql/libsql