Assume that you use Microsoft SQL Server 2012 or SQL Server 2014. When you run a query to update a table that has an XML calculated column, an access violation exception occurs. The query works correctly after you drop the constraints of the table. An access violation occurs again when you try to re-add the constraints. You receive the following error:
A severe error occurred on the current command. The results, if any, should be discarded.
An internal metadata object is reset incorrectly. This leads to the exception.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.