code: function DatabaseError( code, message ) {
    Error.captureStackTrace( this, DatabaseError )
    this.name = DatabaseError.name
    this.code = code
    this.message = message
  }
docs: @link https://stackoverflow.com/questions/1382107/whats-a-good-way-to-extend-error-in-javascript#answer-35966534
  
  @param {number} code
  @param {string} message
  
  @constructor