sqlite-memory-vfs VS go-sqlite3

Have now implemented a version of this at https://github.com/michalc/sqlite-memory-vfs/blob/74a24ce567...

I think different to yours in two ways:

- If doesn't go via PENDING if it doesn't need to. Not sure what's best really - but since RESERVED can already be skipped in some cases (recovering from a hot-journal) then so far happy with "skipping is a thing", and PENDING is private to the VFS anyway from what I can tell, so nothing else should care I think

- It doesn't do the blocking on PENDING in the lock function, but depends on SQLite's core code doing it via the busy handler/timeout

Yep, I just made it tweakable at build, which was always the intent, although I expect the default to be popular.

https://github.com/ncruces/go-sqlite3/blob/67d859a5/vfs/adia...

That's unfortunate about the default parameters, but note that you can also replace the KDF altogether (besides just not using it).

You just need to implement this interface, with any HBSH construction and KDF:

https://github.com/ncruces/go-sqlite3/blob/67d859a5/vfs/adia...

If you keep the HBSH and change the KDF, your file format will be “compatible.”

struggling figuring out how to make my cgo sqlite cross-compile to Windows

Plenty of people trying to fix that.

There's at least:

https://modernc.org/sqlite

Then there's https://github.com/zombiezen/go-sqlite that actually builds https://crawshaw.io/sqlite on top of modernc.

And there's mine that has both a low level and a database/sql driver builds and runs everywhere Go does: https://github.com/ncruces/go-sqlite3

If you're interested both SQLite's and my memdb VFSes implement safe locking.

Depending on your familiarity with Go, mine maybe easier to follow, or not.

https://github.com/ncruces/go-sqlite3/blob/f1b00a9944730eaa9...

One thing I tried to make sure, to avoid the pitfall modernc is having, is to make sure building "the WASM BLOB" is easily reproducible with widely available tools:

https://github.com/ncruces/go-sqlite3/blob/main/.github/work...

I do apply some light patches to SQLite, but so far they've always cleanly applied, and I can produce a new release within hours of being notified of SQLite releases.

Disclosure: I'm working on alternative Cgo-less bindings for SQLite, using wazero.

https://github.com/ncruces/go-sqlite3

One of the problems of the modernc approach (IMO) is that they're not just transpiring CPU/compute stuff, but entirely OS/platform stuff.

Each Go file of theirs is a xxx_os_arch.go that starts with 100s of OS-#defines-as-consts, and goes on to transpile fully #ifdefed code.

It also implements antithetical (in Go) stuff like goroutine local storage, because libc pthreads can't live without it.

And all IO is via direct syscalls that will never play nice with the Go scheduler, because, again this is OS level stuff.

WASM defines a cross platform CPU and an ABI, and using that for compute and the bottom OS layer in Go you get (IMO) a nicer end result.

Given the hard task of generating decent code from WASM at load time (wazero's compiler is pretty naive, a better one is being developed, but it will take seconds to generate good code for anything non trivial like SQLite) I wouldn't mind having a solution that translated to Go, or Go ASM, at build time.

The github.com/ncruces/go-sqlite3 is a link.

Using the stack pointer global is an interesting hack. I'd never thought of that. Need to compare with what I'm doing for SQLite (a kind of per connection arena).