New SCV constraint type

New SCV constraint type Unique Key (UK) is now available. Unique Keys can be used in SCV validation rules to check uniqueness of imported data records. UK constraints extend the existing PK and BK constraints:

• UK constraints allow enforcing uniqueness of imported data records using columns other than the PK columns.
• UK constraints allow defining uniqueness checks on columns wherein one or more columns can be empty (which is not possible when PK is used).