What is Domain-Key Normal Form (DK/NF)

Domain-Key Normal Form (DK/NF) is a level of database normalization that ensures a table is free from redundancy and anomalies by enforcing strict rules on attribute domains and keys. A table is in DK/NF if:

1. **Domain Constraints:** Every attribute in the table conforms to its domain (allowed values and data types).

2. **Key Constraints:** All constraints are implied by the table’s candidate keys, meaning any constraints on non-key attributes are dependent on candidate keys.

In DK/NF, every constraint on the table should be enforceable by its candidate keys, ensuring a high degree of normalization and reducing redundancy.