lvl. 1 Chapter 2 Relational Model (QB)

The number of tuples in a relation is known as

• degree
• relation
• attribute
• cardinality

Which of the following aspects of data is the concern of a relational database model?

• data manipulation
• data integrity
• data structure
• all of these

A relational database consists of a collection of

• Tables
• Fields
• Records
• Keys

Which of the following is used to denote the selection operation in relational algebra?

• Pi (Greek)
• Sigma (Greek)
• Lambda (Greek)
• Omega (Greek)

For select operation the                  appear in the subscript and the                        argument appears in the paranthesis after the sigma.

• Predicates, relation
• Relation, Predicates
• Operation, Predicates
• Relation, Operation

The                        operation, denoted by −, allows us to find tuples that are in one relation but are not in another.

• Union
• Set-difference
• Difference
• Intersection

A Set of Possible data value is called                                              .

• Attribute
• Degree
• Tuple
• Domain

A list of records that satisfies a particular condition is displayed using operation.

• Select
• Project
• Union
• Cross Product

The minimal set of attributes that can uniquely identify a tuple is known as a .

• Candidate key
• Canon key
• Super key
• Superb key

The Statement that requests a retrieval of information from database is called as

• Control Statement
• Query
• Manipulation Statement
• Both A & B