Which statement best describes the GROUPING function?
It is used to set the order for the groups to be used for calculating the grand totals and subtotals.
It is used to form various groups to calculate total and subtotals created using ROLLUP and CUBE operators.
It is used to identify if the NULL value in an expression is a stored NULL value or created by ROLLUP or CUBE.
It is used to specify the concatenated group expressions to be used for calculating the grand totals and subtotals.