September 2010
Intermediate to advanced
1704 pages
111h 8m
English
GROUPING SETSThe CUBE and ROLLUP operators allow you to run a single query and generate multiple sets of groupings. However, the sets of groupings are fixed. For example, if you use GROUP BY ROLLUP (A, B, C), you get aggregates generated for the following groupings of nonaggregate columns:
• GROUP BY A, B, C
• GROUP BY A, B
• GROUP BY A
• A super-aggregate for all rows
If you use GROUP BY CUBE (A, B, C), you get aggregates generated for the following groupings of nonaggregate columns:
• GROUP BY A, B, C
• GROUP BY A, B
• GROUP BY A, C
• GROUP BY B, C
• GROUP BY A
• GROUP BY B
• GROUP BY C
• A super-aggregate for all rows
SQL Server 2008 introduces the GROUPING SETS operator in addition to the CUBE and ROLLUP operators for performing several ...