Podcast
Questions and Answers
Relational algebra is a theory that uses algebraic structures for modeling data.
Relational algebra is a theory that uses algebraic structures for modeling data.
True (A)
The main application of relational algebra is to provide a theoretical foundation for object-oriented databases.
The main application of relational algebra is to provide a theoretical foundation for object-oriented databases.
False (B)
Unary operators in relational algebra accept two relations as input.
Unary operators in relational algebra accept two relations as input.
False (B)
Natural join is a unary operator.
Natural join is a unary operator.
The result of the Cartesian product is a set of (n+m)-tuples.
The result of the Cartesian product is a set of (n+m)-tuples.
Projection is a binary operation.
Projection is a binary operation.
The result of a selection operation is a relation that contains every attribute of every unique record.
The result of a selection operation is a relation that contains every attribute of every unique record.
True or false: The natural join is the relational counterpart of the logical OR operator.
True or false: The natural join is the relational counterpart of the logical OR operator.
Which type of query language takes instances of relations as input and yields instances of relations as output?
Which type of query language takes instances of relations as input and yields instances of relations as output?
Which operator in relational algebra is used to select tuples from a relation based on some condition?
Which operator in relational algebra is used to select tuples from a relation based on some condition?
What is the result of a projection operation in relational algebra?
What is the result of a projection operation in relational algebra?
Which operator in relational algebra is used to join two relations?
Which operator in relational algebra is used to join two relations?
What is the purpose of the rename operation in relational algebra?
What is the purpose of the rename operation in relational algebra?
Which operator in relational algebra gives a relation with tuples that are in the first relation but not in the second relation?
Which operator in relational algebra gives a relation with tuples that are in the first relation but not in the second relation?
Which operator in relational algebra is used to filter certain attributes or tuples from an input relation?
Which operator in relational algebra is used to filter certain attributes or tuples from an input relation?
Which of the following is a requirement for the Cartesian product to be defined?
Which of the following is a requirement for the Cartesian product to be defined?
What does the natural join operator in relational algebra do?
What does the natural join operator in relational algebra do?
Which of the following statements is true about the left outer join operator in relational algebra?
Which of the following statements is true about the left outer join operator in relational algebra?
What is the main purpose of the theta-join operator?
What is the main purpose of the theta-join operator?
What is the division operation in relational algebra?
What is the division operation in relational algebra?
Flashcards are hidden until you start studying
