Mydown NPM | npm.io

MyDOWN

MySQL as a LevelUP backend with multi table support. Inspired from SQLdown, MyDOWN leverages node-mysql with simplified queries for better performance.

npm install mydown

mydown = require('mydown')(database, config)

MyDOWN factory. Supply MySQL connection options and pool options as config.

//MyDOWN factory
var mydown = require('mydown')('db', {
  connectionLimit: 10,
  host: 'localhost',
  user: 'bob',
  password: 'secret'
})

Database needs to be created before initializing MyDOWN:

mysql -uroot -p -e "CREATE DATABASE IF NOT EXISTS db"

levelup(table, { db: mydown })

MyDOWN consumed by LevelUP, where location argument defines the table.

options.prefix

MyDOWN batch() is a transactional operation that can be applied into multiple tables, by setting the options.prefix property.

//tables a, b, c
var a = levelup('a', { db: mydown })
var b = levelup('b', { db: mydown })
var c = levelup('c', { db: mydown })

a.batch([
  { type: 'put', key: 'foo', value: 'a' },
  { type: 'put', key: 'foo', value: 'b', prefix: b }, //levelup prefix
  { type: 'put', key: 'foo', value: 'c', prefix: 'c' } //string prefix
], function () {
  a.get('foo', function (err, val) {
   //val === 'a'
  })
  b.get('foo', function (err, val) {
   //val === 'b'
  })
  c.get('foo', function (err, val) {
   //val === 'c'
  })
})

Tests

Abstract-LevelDOWN test suite is green except for 'implicit iterator snapshot'. This is because 'implicit snapshot' is not the default behavior of a transactional database. Implementing this would require more complicated query and schema, thus bad performance for very little gain in real-world use cases.