Repeaters operate in
i) Physical layer
ii) Datalink layer
iii) Transport layer
iv) Network layer
i and ii only
ii and iii only
ii only
i only
Correct Answer :
D. i only
Related Questions
The privilege lists include
i) select
ii) insert
iii) update
iv) delete
only i)
only i) ii)
only i) ii) iii)
i) ii) iii) iv)
The output of the Data Definition Language is stored in the
view table
schema
metadata
all of the above.
In this data model each record can hae more than one parent
Hierarchical model
E-R model
Network based model
none of these
A functional dependency between two or more non-key attributes is called
Transitive dependency
Partial transitive dependency
Functional dependency
Partial functional dependency
Which of the following Key is used to represent relationship between the tables?
Primary key
Secondary Key
Foreign Key
None of these
The method by which the structure of the database is modified to eliminate hidden dependencies and replacing groups is
Normalization
Indexing
Enforcing referential integrity
Enforcing data integrity
DBMS utility which allows to reconstruct the correct state of database from the backup and history of transactions
Backup
Recovery
Grant
Troubleshooting
Relational Algebra is
Data Definition Language.
Data Manipulation Language
Procedural query Language
None of the above
The union of primary keys of a related entity becomes …………. Of a relation.
primarykey
superkey
candidatekey
foreignkey
Thermal noise is often referred to as ............... noise, because it affects uniformly the different frequencies.
Gray
White
Blue
Black
A table that displays data redundancies yields ____________ anomalies
Insertion
Deletion
Update
All of the above
Tertiary storage
magnetic tape
juke box
optical disk
All of the above
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
The statement
Every foreign-key value must match a primary-key value in an associated table
Is related to
View
Cursor defination
Referential intergrity
Trigger
Which of the following operator preserves unmatched rows of the relations being joined?
Inner join
Outer join
union
Intersect
Noiseless channel has ……… types of protocols.
2
3
4
5
Related fields in a database are grouped to form a
data file.
data record.
menu.
bank.
It is possible to define a schema completely using
VDL and DDL.
DDL and DML.
SDL and DDL.
VDL and DML.
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)
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
The syntax to select all column from the table is
select all from tablename
select * from tablename
select from tablename
none of these
The statement in SQL which allows to change the definition of a table is
Select
Update
Create
Alter
Specialization is a
top-down approach.
bottom-up approach.
left-right approach.
none of the above
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 B) and C).
Data fragmentation is performed by the …… and each fragment is stored at…………..
DBMS, same site
OS ,same site
DBMS ,different site
OS ,different site
Which of the following works as a filter?
UPDATE
DROP
ALTER
SELECT
Which of the following extracts its data from the result of an SQL SELECT statement.
View
Synonym
Sequence
Transaction
Primary storage
magnetic disk
magnetic tape
juke box
cache
Which of the following concurrency control schemes is not based on serializability property?
Two-phase locking
Timestamped based locking
Graph-based locking
none of the above
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