A Formal Approach to Null Values in Database Relations.
Joachim BiskupPublished in: Advances in Data Base Theory (1979)
Keyphrases
- null values
- integrity constraints
- database
- relational databases
- normal form
- databases
- query evaluation
- incomplete information
- data dependencies
- relational algebra
- functional dependencies
- relational database theory
- containment of conjunctive queries
- update operations
- predicate logic
- database design
- database schema
- data model
- relational database systems
- universal relation
- database systems
- relational calculus
- query language
- database applications