docs: function watch(keys, database) {
  
    keys = keys.map(function(k) {
      if(k instanceof Buffer) return k.toString();
      return k;
    })
  
    //console.dir(keys);
  
    // watch can be called multiple times
    // with the same keys, prevent listener leaks
    this.unwatch(database);
  
    database.on('write', this.onWrite);
    this.watched = keys;
  }