Error Message:
Msg 243, Level 16, State 1, Line 1
Type %1! is not a defined system type.
Severity level:
16.
Description:
This error message appears when you try to use a datatype that is not known and supported by SQL Server.
Consequences:
The T-SQL statement can be parsed, but causes the error at runtime.
Resolution:
Error of the Severity level 16 are generated by the user and can be fixed by the SQL Server user. The datatype must be known to SQL Server. Either as a system-supplied datatype or as user-defined datatype (UDT; SQL Server 2005).
Versions:
All versions of SQL Server.
Example(s):
SELECT CAST(‘257’ AS MyType)
Remarks:
In the above example we try to convert the string 257 to the MyType datatype. Because this datatype is neither system-supplied nor known to SQL Server as UDT, the error is raised.