Quiz Discussion

The most commonly used operation in relational algebra for projecting a set of tuple from a relation is

• 1]

  Join

• 2]

  Projection

• 3]

  Select

• 4]

  Union

Student(ID, name, dept name, tot_cred)
In this query which attributes form the primary key?

• 1]

  Name

• 2]

  Dept

• 3]

  Tot_cred

• 4]

  ID

For each attribute of a relation, there is a set of permitted values, called the ________ of that attribute.

• 1]

  Domain

• 2]

  Relation

• 3]

  Set

• 4]

  Schema

The _________ provides a set of operations that take one or more relations as input and return a relation as an output.

• 1]

  Schematic representation

• 2]

  Relational algebra

• 3]

  Scheme diagram

• 4]

  Relation flow

_____ operator is used for appending two strings.

• 1]

  &

• 2]

  %

• 3]

  ||

• 4]

  _

SELECT name
FROM instructor
WHERE dept name = ’Physics’
ORDER BY name;

By default, the order by clause lists items in ______ order.

• 1]

  Descending

• 2]

  Any

• 3]

  Same

• 4]

  Ascending

Database __________ which is the logical design of the database, and the database _______ which is a snapshot of the data in the database at a given instant in time.

• 1]

  Instance, Schema

• 2]

  Relation, Schema

• 3]

  Relation, Domain

• 4]

  Schema, Instance

Which one of the following is procedural language?

• 1]

  Domain relational calculus

• 2]

  Tuple relational calculus

• 3]

  Relational algebra

• 4]

  Query language

A domain is atomic if elements of the domain are considered to be ____________ units.

• 1]

  Different

• 2]

  Indivisbile

• 3]

  Constant

• 4]

  Divisible

’_____’ matches any string of ______ three characters. ’_____%’ matches any string of at ______ three characters.

• 1]

  Atleast, Exactly

• 2]

  Exactly, Atleast

• 3]

  Atleast, All

• 4]

  All, Exactly