public function getLocalKeys($relation)
    {
        return isset($this->localForeignKeys[$relation]) ? $this->localForeignKeys[$relation] : null;
    }
public function getLocalKeys($relation)
    {
        return isset($this->localForeignKeys[$relation]) ? $this->localForeignKeys[$relation] : null;
    }
public function getLocalKeys ( $ relation ) { return isset ( $ this -> localForeignKeys [ $ relation ] ) ? $ this -> localForeignKeys [ $ relation ] : null ; }
Return the local keys associated to the relationship.

@param string $relation

@return string|array|null
Return the local keys associated to the relationship .