MyDB

A simple key-value database implementation from scratch in Rust under 300 lines of code.

More specifically, it is a reimplemation in Rust of the didactic database CaskDB which is itself inspired by Bitcask.

Features

• Key/Value data model
• Embedded (use as a library, no client/server)
• Disk-based persistence
• No runtime dependencies

Limitations

• Keys and values are limited to UTF-8 encoded strings
• No delete operation
• No range queries
• No concurrency controls
• Memory usage might be high with a lot of keys
• Startup time might be slow because we need to load all keys from disk to memory

Usage

use mydb::{MyDB, Result};

fn main() -> Result<()> {
    let filename = "data.db";
    let mut db = MyDB::new(filename)?;

    db.set("hello", "world")?;
    assert_eq!(db.get("hello")?, Some("world".to_string()));

    assert_eq!(db.get("nokey")?, None);

    Ok(())
}

Development

Run tests:

cargo test

Build for release:

cargo build --release

License

See LICENSE.