Electromagnetic spectrum included in radiowaves are
i) Super High Frequency (SHF)
ii) Very High Frequency (VHF)
iii) Ultra High Frequency (UHF)
iv) High Frequencies (HF)
i, ii and iii only
i, ii and iv only
ii, iii and iv only
i, iii and iv only
Correct Answer :
C. ii, iii and iv only
Related Questions
In an Entity-Relationship Diagram Ellipses represents
Attributes
Weak entity set
Relationship sets
Multi-valued attributes
A type of query that is placed within a WHERE or HAVING clause of another query is called
Super query
Sub query
Master query
Multi-query
Benefit of database normalization is
smaller number of tables
higher query processing efficiency
reduced I/O for most queries
reduced data redundancy
Which of the following file organization provides very fast access to any arbitrary record of a file?
Ordered file
Unordered file
Hashed file
B-tree
The minimal set of super key is called
Primary key
Secondary key
Candidate key
Foreign key
Transaction processing is associated with everything below except
producing detail, summary, or exception reports.
recording a business activity.
confirming an action or triggering a response.
maintaining data.
Functional dependencies are generalization of
Relation dependencies
Data dependencies
key dependencies
none of the above
A composite attribute is converted to individual attributes in which of the following normal form ?
first
Second
third
fourth
Specialization is a
top-down approach.
bottom-up approach.
left-right approach.
none of the above
Which of the following operator preserves unmatched rows of the relations being joined?
Inner join
Outer join
union
Intersect
Which of the following is also known as Offline storage ?
primary storage
secondary storage
tertiary storage
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
In two-phase locking
the data items are locked in growing phase.
the data items are released in shrinking phase.
Both A and B are true
Both A and B are false
Object based data models are used in describing the abstraction of the following levels?
Conceptual and view
Only physical
Physical and conceptual
Only conceptual
The command used to delete a particular column in a relation
UPDATE
DROP
ALTER
DELETE
A fragmentation is categorized in
1 part
2 part
3 part
4 part
Volatile storage
loses its contents when power is switched off.
doesnt loses its contents when power is switched off.
creates backup when power is switched off.
none
The host part in a class A type of an IP address has
12 bits
16 bits
24 bits
28 bits
The syntax to select all column from the table is
select all from tablename
select * from tablename
select from tablename
none of these
Which of the following aggregate function doesnt ignore NULLs in its results?
COUNT
COUNT(*)
MAX
none of these
When all attributes in a relation tuple are not functionally dependent only on the key attribute. Which of the following normalization is needed?
first
second
third
fourth
The database environment has all of the following components except:
users.
separate files.
database.
database administrator.
Tape storage is referred to as
sequential access storage
direct access storage
random access storage
none of the above
The union of primary keys of a related entity becomes …………. Of a relation.
primarykey
superkey
candidatekey
foreignkey
Which of the following extracts its data from the result of an SQL SELECT statement.
View
Synonym
Sequence
Transaction
Which of the following layer uses trailer of the frame for error detection?
Transport layer
Network layer
Datalink layer
None of these
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
Three SQL, DDL, CREATE commands are
Schema, Base and Table
Schema, Table and View
Base, Table and Schema
Key, Base and Table
Data fragmentation is performed by the …… and each fragment is stored at…………..
DBMS, same site
OS ,same site
DBMS ,different site
OS ,different site
QBE
Query By Execution
Query By Example
Query By Extraction
None of the above.