/**
  * {@inheritdoc}
  */
 public function walkPathExpression($pathExpr)
 {
     if (!$this->inSubSelect && !$this->platformSupportsRowNumber() && !in_array($pathExpr, $this->orderByPathExpressions)) {
         $this->orderByPathExpressions[] = $pathExpr;
     }
     return parent::walkPathExpression($pathExpr);
 }
 /**
  * {@inheritdoc}
  */
 public function walkPathExpression($pathExpr)
 {
     if (!in_array($pathExpr, $this->orderByPathExpressions)) {
         $this->orderByPathExpressions[] = $pathExpr;
     }
     return parent::walkPathExpression($pathExpr);
 }