Keyphrases
- relational algebra
- relational calculus
- database query languages
- expressive power
- relational model
- query language
- normal form
- data model
- relational database systems
- complex objects
- relational operators
- first order logic
- transitive closure
- relational data model
- database
- relational databases
- aggregate functions
- null values
- type checking
- management system
- join operator
- summary tables
- algebraic operations
- database technology
- functional dependencies
- database systems
- data mining