In an Entity-Relationship Diagram Diamonds represents
Attributes
Multi-valued attributes
Weak entity set
Relationship sets
Correct Answer :
D. Relationship sets
Related Questions
The collection of information stored in a database at a particular moment is?
View
Instance
Scheme
None of these
View never contains derived columns.
True
False
Cant say
none
Object based data models are used in describing the abstraction of the following levels?
Conceptual and view
Only physical
Physical and conceptual
Only conceptual
Tertiary storage
magnetic tape
juke box
optical disk
All of the above
Primary storage
magnetic disk
magnetic tape
juke box
cache
Cross Product is a:
Unary Operator
Binary Operator
Ternary Operator
none of the above
Which of the following is not an Aggregate function?
Min
Max
Select
Avg
In an object oriented model, one object can access data of another object by passing?
Instance variable
Variable
Message
Function
The raw facts and figures are:
Data
Data field
DBMS
DBASE
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 types of noiseless channels are
i) Selective Reject ARQ
ii) simplest protocol
iii) Go-Back-N ARQ
iv) Stop-and-Wait Protocol
i, ii only
ii and iv only
ii and iv only
i, iv only
What is the max data capacity of STP?
1 Gbps
56 Mbps
100 Mbps
256 Mbps
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
Tape storage is referred to as
sequential access storage
direct access storage
random access storage
none of the above
The control of concurrent execution is left with the
operating system
controller unit of the kernel
concurrency control component of the database system
none
The syntax to select all column from the table is
select all from tablename
select * from tablename
select from tablename
none of these
The maximum number of children in a B-tree of order m is
m+1
m
m-1
m/2
Three SQL, DDL, CREATE commands are
Schema, Base and Table
Schema, Table and View
Base, Table and Schema
Key, Base and Table
The index table has …… Columns.
1
2
3
4
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
A composite attribute is converted to individual attributes in which of the following normal form ?
first
Second
third
fourth
Which of the following is a classical approach to database design?
Left Right approach
Right Left approach
Top Down approach
Bottom Up approach
Which of the following operator preserves unmatched rows of the relations being joined?
Inner join
Outer join
union
Intersect
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
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
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
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 method of access which uses key transformation is known as
direct.
hash.
random.
sequential.
Transaction access data using two operations
read(), print()
read(), write()
scan(), write()
none of the above
Aggregate functions are also called
serial functions
non-serial functions
row functions
column functions