A file manipulation command that extracts some of the records from a file is called
SELECT
PROJECT
JOIN
PRODUCT
Who is responsible for managing and controlling the activities associated with the database ?
Database administrator
Programmer
Naive user
End user
How many distinct tuples are there in a relation instance with cardinality 22 ?
22
11
1
none
In the relational model, cardinality is the
number of tuples
number of attributes
number of tables
number of constraints
Data independence means
data is defined separately and not included in programs
programs are not dependent on the physical attributes of data
programs are not dependent on the logical attributes of data
both 2 and 3
In a relational model, relations are termed as
tuples
attributes
tables
rows
Which of the following operations is used if we are interested only in certain columns of a table ?
PROJECTION
SELECTION
UNION
In the abstraction of a database system the external level is the
physical level
logical level
conceptual level
view level
In a table Employee Emp- code, Pan_ no are the candidate keys. If Emp_ code is taken as the primary key then Pan_ no is _________ key.
candidate key
alternate key
primary key
foreign key
Key to represent relationship between tables is called
