Join::__construct PHP Method

    public function __construct($leftRightOrFull, $innerOuterOrCross, $table, $tablePrimaryKey, $fromTableForeignKey, $natural = '')
    {
        $this->natural = $natural;
        $this->leftRightOrFull = $leftRightOrFull;
        $this->innerOuterOrCross = $innerOuterOrCross;
        $this->table = $table;
        $this->tablePrimaryKey = $tablePrimaryKey;
        $this->fromTableForeignKey = $fromTableForeignKey;
    }

 /**
  * Construct a Columnar join object.
  *
  * @param string[] $columns
  * @param array    $keys
  * @param string   $jointKey
  * @param bool     $useAlphaNumMatch
  */
 public function __construct(array $columns, array $keys = ['id'], $jointKey = 'joint_data', $useAlphaNumMatch = true)
 {
     parent::__construct($useAlphaNumMatch);
     $this->columns = array_flip($columns);
     $this->jointKey = $jointKey;
     $this->keys = array_flip($keys);
 }