4 stable releases

1.0.3 Jun 21, 2020

#156 in Database implementations

Apache-2.0

59KB
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Rust 861 SLoC // 0.1% comments C 574 SLoC // 0.1% comments

MHdb

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MHdb is a pure Rust database implementation, based on dbm.

See crate documentation.

Changelog

v1.0.3

  • Update Cargo.toml

v1.0.2

  • Update Cargo.toml

v1.0.1

  • Update docs

v1.0.0

  • Initial release

lib.rs:

MHdb is a pure Rust embedded key-value store database, based on dbm.

Simple use

use mhdb::{Db, prelude::*};

let mut db = Db::open("mydb")?;
let key = "Number".to_owned();
let val = 42i32;

db.store(key.clone(), val)?;

let num: Option<i32> = db.fetch(42u8)?;
assert_eq!(num, Some(val));
println!("{}", num.unwrap());

Any type implementing Datum can be stored in the database.

Datum

A datum represents a single item in the database. Types used as keys and/or values must therefore implement the Datum trait.

Datum is automatically implemented on any type implementing the Serde traits Serialize and Deserialize.

In-memory database

Any type which implements the Source trait can be used as database sources. This trait is in turn automatically implemented for any type which implements the Read, Write, Seek, Sync, and Send standard library traits. A vector may therefore be used as an in-memory database.

use mhdb::{Db, prelude::*};
use std::io::Cursor;

let dirf = Cursor::new(Vec::<u8>::new());
let pagf = Cursor::new(Vec::<u8>::new());
let mut db: Db = Db::with_sources(Box::new(pagf), Box::new(dirf))?;

db.store(42u8, "Hello world".to_owned())?;
let txt: Option<String> = db.fetch(42u8)?;
assert!(txt.is_some());
println!("{}", txt.unwrap());

Limitations

  • Key-value pairs can not be larger than 506B
  • Db objects are not thread safe

Dependencies

~235KB