Msg 305, Level 16, State 1, Line 2
The xml data type cannot be compared or sorted, except when using the IS NULL operator.
This error message appears when you try to group by a column of the data type XML.
The T-SQL statement can be parsed, but causes the error at runtime.
Error of the Severity Level 16 are generated by the user and can be fixed by the SQL Server user. You cannot use a XML column in a GROUP BY clause.
This error message was introduced with SQL Server 2005.
IF OBJECT_ID(‘tempdb..#t’) > 0
DROP TABLE #t
CREATE TABLE #t
INSERT INTO #t SELECT ‘1’;
GROUP BY c1
In the above example we try to group by the c1 column. Because this is a column of the XML data type, the error is raised.