addSortAggregate example

/** * {@inheritdoc} */
  public function execute() {
    return $this
      ->prepare()
      ->addAggregate()
      ->compile()
      ->compileAggregate()
      ->addGroupBy()
      ->addSort()
      ->addSortAggregate()
      ->finish()
      ->result();
  }

  /** * {@inheritdoc} */
  public function prepare() {
    parent::prepare();
    // Throw away the id fields.     $this->sqlFields = [];