Keyphrases
- relational calculus
- relational algebra
- expressive power
- query language
- relational model
- complex objects
- normal form
- arithmetic constraints
- relational data model
- data model
- first order logic
- relational databases
- database
- transitive closure
- database query languages
- incomplete information
- database technology
- relational database systems
- relational data
- object oriented
- database systems
- data mining