Nils Gustav Stråbø (11/10/2011)
Good question, but I'm not sure that the explanation is 100% correct.
I'm sure that the part of the explanation was deleted by accident:
Because values from different data type families must be explicitly cast before being referenced in comparison predicates, the effects of the something is missing here The values in the following table are examples of the rules regarding data type precedence.
I think the meaning of the explanation is that a programmer must use something like "CAST(sql_variant_value AS datatype)" or "CONVERT(datatype, sql_variant_value, style)" rather than "sql_variant_value" by itself.