Specialization is a
top-down approach.
bottom-up approach.
left-right approach.
none of the above
Correct Answer :
A. top-down approach.
Related Questions
The left outer join takes all tuples
in the left relation which didnt match with any tuple in right relation
in the left relation which matched with a tuple in right relation
in the right relation which didnt match with any tuple in left relation
in the right relation which matched with a tuple in left relation
In an E-R diagram attributes are represented by
rectangle.
square.
ellipse.
triangle.
A fragmentation is categorized in
1 part
2 part
3 part
4 part
Attenuation can be also expressed in decibel dB) and commonly used because.
i) Signal strengths often fall off logarithmically
ii) Cascade losses and gains can be calculated with simple additions and subtractions
i only
ii only
Both A and B
None of the above
Aggregate functions are also called
serial functions
non-serial functions
row functions
column functions
Which of the following aggregate function doesnt ignore NULLs in its results?
COUNT
COUNT(*)
MAX
none of these
Which of the following is true statement ?
SQL permits attribute names to be repeated in the same relation.
a SQL query automatically eliminates duplicates.
a SQL query will not work if there are no indexes on the relations
None of these
In defining the notion of the tuple variable, which one of the clause is useful?
as
by
from
none of the above
Data fragmentation is performed by the …… and each fragment is stored at…………..
DBMS, same site
OS ,same site
DBMS ,different site
OS ,different site
A table that displays data redundancies yields ____________ anomalies
Insertion
Deletion
Update
All of the above
Transaction access data using two operations
read(), print()
read(), write()
scan(), write()
none of the above
Select the incorrect statement(s)
i) Foreign key values can be left blank
ii) In SQL duplicates may be present
iii) Theta join operation doesnt remove duplicate columns.
iv) NULL value means string of blank characters.
i ,iii only
ii, iv only
iii, iv only
ii, iii, iv
In RDBMS, Data is presented as a collection of
Relation
Table
Attribute
Entity
A relation is said to be in ………. If it doesnt contain partial dependency
1NF
2NF
3NF
BCNF
By default a user who has been granted some form of authorization
is allowed to pass them to others
is not allowed to pass them to others
may be or may not be allowed to pass them to others
none
In which of the following SET concept is used ?
Network Model
Hierarchical Model
Relational Model
None of these
Consider the join of a relation R with relation S. If R has m tuples and S has n tuples,
then the maximum size of join is:
mn
m+n
m+n)/2
2 m+n)
Mail services are available to network users through the
Session layer
Presentation layer
Application layer
Transport layer
.................. occurs due to velocity of propagation the frequency varies. Thus various frequency components of a signal arrive at the receiver at different times.
Noise
Delay distortion
Attenuation distortion
Dispersion
What is the max data capacity of STP?
1 Gbps
56 Mbps
100 Mbps
256 Mbps
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.
Encoding method which does not provide for synchronization
B8ZS
Manchester
RZ
NRZ-L
Select the correct
i) A timestamp-based scheduler cant produce live lock
ii) Aggregate functions cant appear with HAVING clause.
iii) Isolation is a property of database transaction.
i and ii only
ii and iii only
i and iii only
i only
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
Which of the following is a classical approach to database design?
Left Right approach
Right Left approach
Top Down approach
Bottom Up approach
Datalog is
procedural query language
nonprocedural query language
scan(), write()
none of the above
The host part in a class A type of an IP address has
12 bits
16 bits
24 bits
28 bits
Related fields in a database are grouped to form a
data file.
data record.
menu.
bank.
In a Hierarchical model records are organized as
Graph.
List.
Links.
Tree.
The access protocol used by traditional Ethernet
CSMA/CA
CSMA/CD
CSMA
Token ring