[LMDB](https://www.symas.com/lmdb) (Lightning Memory-Mapped Database) is an embedded transactional database in the form of a key-value store. It can handle vast amounts of data and is comparable in speed to [MMKV](https://github.com/Tencent/MMKV).
This package embeds & provides React Native bindings for LMDB.
## Installation
```sh
npm install react-native-lmdb
cd ios && pod install
```
## Usage
```js
import { open } from 'react-native-lmdb';
// Define the largest size of the db (100mb in this case)
const mapSize = 1024 * 1024 * 100;
const { put, get, del } = open('mydb.mdb', mapSize);
put('key1', 'value1');
put('key2', 'value2');
console.log(get('key1'));
console.log(get('key2'));
del('key1');
del('key2');
```
## Motivation
MMKV is a great tool but isn't designed for vast amounts of data.
When setting and getting 10_000 large strings:
| DB | Empty | Run 1 | Run 2 | Run 3 |
| ---- | ----- | ------ | ------ | ------ |
| mmkv | 16kb | 33.6mb | 67.1mb | 67.1mb |
| lmdb | 33kb | 38.3mb | 38.3mb | 38.3mb |
// @TODO - check db sizes on devices
SQLite can handle vast amounts of data but is async thus increases complexity and introduces possible race conditions.
LMDB is mature, synchronous, and can handle anything you throw at it. 💪
## Goals of this Project
- Simple API
- Performance over features
## Benchmarks
NOTES: these numbers might not represent current state. I am still in the process of profiling and optimising.