redb 0.21.0

Rust Embedded DataBase


CI Documentation License dependency status

A simple, portable, high-performance, ACID, embedded key-value store.

redb is written in pure Rust and is loosely inspired by lmdb. Data is stored in a collection of copy-on-write B-trees. For more details, see the design doc

use redb::{Database, Error, ReadableTable, TableDefinition};

const TABLE: TableDefinition<&str, u64> = TableDefinition::new("my_data");

fn main() -> Result<(), Error> {
    let db = Database::create("my_db.redb")?;
    let write_txn = db.begin_write()?;
        let mut table = write_txn.open_table(TABLE)?;
        table.insert("my_key", &123)?;

    let read_txn = db.begin_read()?;
    let table = read_txn.open_table(TABLE)?;
    assert_eq!(table.get("my_key")?.unwrap().value(), 123);



redb is undergoing active development, and should be considered beta quality. It may eat your data, and does not have any guarantees of file format stability :)


  • Zero-copy, thread-safe, BTreeMap based API
  • Fully ACID-compliant transactions
  • MVCC support for concurrent readers & writer, without blocking
  • Crash-safe by default
  • Savepoints and rollbacks


The following features are planned before the 1.0 release

  • Stable file format


redb is nearly as fast as lmdb, and faster than sled, on many benchmarks

redb lmdb rocksdb sled sanakirja
bulk load 4285ms 1031ms 5387ms 5030ms 1000ms
individual writes 229ms 430ms 678ms 650ms 411ms
batch writes 1948ms 1684ms 1027ms 1508ms 2071ms
random reads 948ms 538ms 3112ms 1325ms 622ms
random range reads 2496ms 960ms 5726ms 4493ms 1030ms
random reads (4 threads) 350ms 142ms 1216ms 410ms 277ms
random reads (8 threads) 193ms 77ms 660ms 218ms 844ms
random reads (16 threads) 136ms 45ms 468ms 138ms 4596ms
random reads (32 threads) 118ms 38ms 409ms 119ms 4457ms
removals 4371ms 697ms 2533ms 1943ms 1065ms


Licensed under either of

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Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.