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
Correct Answer :
C. Hashed file
Related Questions
Which of the following is also known as Offline storage ?
primary storage
secondary storage
tertiary storage
none of the above
Specialization is a
top-down approach.
bottom-up approach.
left-right approach.
none of the above
In case of entity integrity, the primary key may be
not Null
Null
both Null & not Null.
any value.
A relation that has no partial dependencies is in which normal form
First
Second
Third
BCNF
An advantage of the database management approach is
data is dependent on programs.
data redundancy increases.
data is integrated and can be accessed by multiple programs.
none of the above.
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)
The syntax to select all column from the table is
select all from tablename
select * from tablename
select from tablename
none of these
In E-R diagram Generalization is represented by
Circle
Rectangle
Hyperbola
Triangle
Which of the following produces the relation that has attributes of R1 and R2
Cartesian product
Difference
Intersection
Product
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
An entity set which have sufficient attributes to form a primary key
Tree structure
Subtree structure
Strong entity set
Table structure
Primary storage
magnetic disk
magnetic tape
juke box
cache
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
A transaction has following states
i) Active
ii) Fail
iii) Abort
iv) Commit
i and ii only
ii and iii only
i and iii only
iii and iv only
Every Boyce-Codd normal form is in
3NF
2NF
1NF
none of the above
DBMS utility which allows to reconstruct the correct state of database from the backup and history of transactions
Backup
Recovery
Grant
Troubleshooting
In RDBMS, Data is presented as a collection of
Relation
Table
Attribute
Entity
Unwanted energy from source other than the transmitter.
Attenuation
Distortion
Delay
Noise
In this data model each record can hae more than one parent
Hierarchical model
E-R model
Network based model
none of these
The minimal set of super key is called
Primary key
Secondary key
Candidate key
Foreign key
The physical location of a record is determined by a mathematical formula that transforms
a file key into a record location is :
B-Tree File
Hashed File
Indexed File
Sequential file.
UML is stands for
Universal Modeling Language
Unified Modeling Language
United Modeling Language
Uni Modeling Language
A relation is said to be in ………. If it doesnt contain partial dependency
1NF
2NF
3NF
BCNF
The method of access which uses key transformation is known as
direct.
hash.
random.
sequential.
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
A logical description of some portion of database that is required by a user to perform task is called as
System View
User View
Logical View
Data View
Tape storage is referred to as
sequential access storage
direct access storage
random access storage
none of the above
The command used to delete a particular column in a relation
UPDATE
DROP
ALTER
DELETE
In an E-R diagram attributes are represented by
rectangle.
square.
ellipse.
triangle.
What are the different types of radio waves that are used for computer network applications?
i) Spread spectrum
ii) High power, single frequency
iii) High power, multiple frequency
iv) Low power, single frequency
v) Low power, multiple frequency
i, ii and iii only
i, ii and iv only
ii, iii and iv only
i, iii and iv only