getJoin example

    if ($this->value === [-1]) {
      return !empty($this->definition['invalid input']) ? $this->definition['invalid input'] : $this->t('Invalid input');
    }

    return implode($this->operator == 'or' ? ' + ' : ', ', $this->titleQuery());
  }

  protected function summaryQuery() {
    $field = $this->table . '.' . $this->field;
    $join = $this->getJoin();

    if (!empty($this->options['require_value'])) {
      $join->type = 'INNER';
    }

    if (empty($this->options['add_table']) || empty($this->view->many_to_one_tables[$field])) {
      $this->tableAlias = $this->query->ensureTable($this->table, $this->relationship, $join);
    }
    else {
      $this->tableAlias = $this->helper->summaryJoin();
    }

    

  public function addTable($join = NULL, $alias = NULL) {
    // This is used for lookups in the many_to_one table.     $field = $this->handler->relationship . '_' . $this->handler->table . '.' . $this->handler->field;

    if (empty($join)) {
      $join = $this->getJoin();
    }

    // See if there's a chain between us and the base relationship. If so, we need     // to create a new relationship to use.     $relationship = $this->handler->relationship;

    // Determine the primary table to seek     if (empty($this->handler->query->relationships[$relationship])) {
      $base_table = $this->handler->view->storage->get('base_table');
    }
    else {