This feature will be removed in a future version of Microsoft SQL Server. Avoid using this feature in new development work, and plan to modify applications that currently use this feature.
The ContactNull property specifies NULL-value handling for catenation.
An expression that evaluates to an object in the Applies To list
TRUE or FALSE
HRESULT GetContactNull(LPBOOL pRetVal);
HRESULT SetContactNull(BOOL NewValue);
If TRUE, A + NULL, where A is a string, yields NULL.
If FALSE, A + NULL, where A is a string, yields A.
Any value for ContactNull is overridden by the AnsiNulls property, which controls NULL catenation behavior for a client session.