Count function in SQL returns the number of
values.
distinct values.
groups.
columns.
Correct Answer :
A. values.
Related Questions
Secondary storage
magnetic disk
magnetic tape
juke box
cache
The minimal set of super key is called
Primary key
Secondary key
Candidate key
Foreign key
Range variables are designed using the
TO clause
FROM clause
RANGE clause
none of the above
A …………… is a memory area where data are processed.
view
trigger
cursor
none of the above
Thermal noise is often referred to as ............... noise, because it affects uniformly the different frequencies.
Gray
White
Blue
Black
Select the incorrect statement
View is derived from other tables.
Once a transaction has executed commit work its effect cant be undone by rollback work .
The input to the aggregate function avg can be non numeric data types
A primary key can never be null.
Which of the following normalization is needed, if an attribute of a composite key is dependent on an attribute of the other composite key?
BCNF
Second
Third
Fourth
Which of the following works as a filter?
UPDATE
DROP
ALTER
SELECT
The mode in which data item may be locked
Partner
Mutual
Exclusive
Atomic
Triggers are also called
active rules
passive rules
inferences
none of the above
As a side-effect of database update ,the system automatically executes a statement called
a view
a grant permission
a trigger
all of the above
Which of the following submit and execute query at run time?
Static SQL
Dynamic SQL
both
none of these
Authorization command in SQL
Allow
Access
Grant
none of the above
An operation that will increase the length of a list is
insert
modify
lookup
none of the above
Query processing is
converting data to insert in a database
translation of query to lower form
range of activities involved in extracting data from a database
none of the above
Tertiary storage
magnetic tape
juke box
optical disk
All of the above
Which of the following statement returns data to the host variables one at a time?
SELECT
RETURN
FETCH
GET
Extended Entity Relationship model consists of which of the following
i) Specialization
ii) Generalization
iii) Categorization
i and ii only
ii and iii only
i and iii only
All i, ii iii
Radio frequencies below ............. are more suitable for omnidirectional applications.
300MHz
1GHz
5GHz
10 GHz
In RDBMS, Data is presented as a collection of
Relation
Table
Attribute
Entity
Which of the following is not an Aggregate function?
Min
Max
Select
Avg
Which of the following are the properties of entities?
Groups
Table
Attributes
Switchboards
The output of the Data Definition Language is stored in the
view table
schema
metadata
all of the above.
Mail services are available to network users through the
Session layer
Presentation layer
Application layer
Transport layer
Multivalued dependency is removed in
4 NF
3 NF
2 NF
1 NF
In an Entity-Relationship Diagram Diamonds represents
Attributes
Multi-valued attributes
Weak entity set
Relationship sets
The database environment has all of the following components except:
users.
separate files.
database.
database administrator.
Referential integrity
controls relationships between operations of an object
controls relationships between instances of a class
controls relationships between attributes in a table
controls relationships between tables in a database
Select the correct statement
i) Aggregate functions work on a group of data and return a single value.
ii) ODBC connects the frontend with the database without considering its compatibility
iii) View definition cant be used at multiple places through with clause .
i and ii only
ii and iii only
i and iii only
i only
A table that displays data redundancies yields ____________ anomalies
Insertion
Deletion
Update
All of the above