NilPortugues\Sql\QueryBuilder\Manipulation\JoinQuery::addJoin PHP Method

    public function addJoin(Select $select, $selfColumn, $refColumn)
    {
        $select->isJoin(true);
        $table = $select->getTable()->getName();
        if (!isset($this->joins[$table])) {
            $newColumn = array($selfColumn);
            $select->joinCondition()->equals($refColumn, SyntaxFactory::createColumn($newColumn, $this->select->getTable()));
            $this->joins[$table] = $select;
        }
        return $this->joins[$table];
    }

 /**
  * @param Select $select
  * @param string $selfColumn
  * @param string $refColumn
  *
  * @return Select
  */
 public function addJoin(Select $select, $selfColumn, $refColumn)
 {
     return $this->joinQuery->addJoin($select, $selfColumn, $refColumn);
 }