Relational Data Model in Database

Relational Data Model in Database

Relational Data Model in Database

  1. Each column in a row must be single valued.
  2. Primary key field value cannot be null.
  3. Primary key must contain unique value.
  4. Foreign key can be null.
  5. Foreign key constraint can contain null values(blank).
  6. If Foreign key is not null , then it must have values that correspond to the value of a primary key in an other relation.
  7. 3NF is adequate for relational database design.
  8. In BCNF we may loose some functional dependencies.