Drops a user-defined datatype.
sp_droptype typename
is the name of a user-defined datatype that you own.
Drops the user-defined datatype named birthday:
sp_droptype birthday
Executing sp_droptype deletes a user-defined datatype from systypes.
A user-defined datatype cannot be dropped if it is referenced by tables or another database object.
Only the Database Owner or datatype owner can execute sp_droptype.
Datatypes User-defined datatypes
System procedures sp_addtype, sp_rename
