Summarizing Data with CUBE and ROLLUP

Is an aggregate function that causes an additional column to be output with a value of 1 when the row is added by either the CUBE or ROLLUP operator, or 0 when the row is not the result of CUBE or ROLLUP?
Grouping is allowed only in the select list associated with a GROUP BY clause that contains either the CUBE or ROLLUP operator.CUBE and ROLLUP function is useful for generating reports. If you’re just doing a simple GROUP BY, with just one GROUP, or multiple GROUPS but with only one possible combination, than use a ROLLUP. The ROLLUP will eliminate showing any values with NULL in the first column.
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