What are the maximum number of Columns in GROUP BY clause in SQL Server?

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What are the maximum number of Columns in GROUP BY clause in SQL Server?
The maximum number of Columns in GROUP BY clause are limited only by number of bytes.

Below link gives details regarding maximum bytes per Group By Clause.
What are the maximum Bytes per GROUP BY in SQL Server?

What are the maximum number of Columns or expressions in GROUP BY WITH CUBE in SQL Server?
The maximum number of Columns or expressions in GROUP BY WITH CUBE is 10 .

What are the maximum number of Columns or expressions in GROUP BY WITH ROLLUP in SQL Server?
The maximum number of Columns or expressions in GROUP BY WITH ROLLUP is 10 .

Max Capacity For SQL Server 2012 SQL Server 2008 R2 SQL Server 2008 SQL Server 2005
maximum number of Columns in GROUP BY clause in SQL Server Limited only by number of bytes. Limited only by number of bytes. Limited only by number of bytes. Limited only by number of bytes.
Maximum number of Columns or expressions in GROUP BY WITH CUBE 10 10 10 10
Maximum number of Columns or expressions in GROUP BY WITH ROLLUP 10 10 10 10

http://msdn.microsoft.com/en-us/library/ms143432.aspx