Symbol to represent weak entity set in ER Model
Dotted rectangle
Square
Doubly outlined rectangle
Diamond
Correct Answer :
C. Doubly outlined rectangle
Related Questions
Which of the following is not a database object?
index
sequence
cursor
trigger
A lock that allows concurrent transactions to access different rows of the same table is known as a
Field-level lock
Row-level lock
Table-level lock
Database-level lock
Database locking concept is used to solve the problem of
Lost Update
Uncommitted Dependency
Inconsistent Data
All of the above
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.
The database environment has all of the following components except:
users.
separate files.
database.
database administrator.
Which of the following statements is not true about two tier client server database architecture?
SQL statements are processed on tier server
SQL statements may be processed on some of the clients
Business logic is mostly processed on clients
Business logic may be processed on the server
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
which of the following is a binary operation?
project
select
rename
none of the above
Object based data models are used in describing the abstraction of the following levels?
Conceptual and view
Only physical
Physical and conceptual
Only conceptual
Radio frequencies below ............. are more suitable for omnidirectional applications.
300MHz
1GHz
5GHz
10 GHz
In the architecture of a database system external level is the
physical level.
logical level.
conceptual level
view level.
Which one of the following statements is false?
The data dictionary is normally maintained by the database administrator.
Data elements in the database can be modified by changing the data dictionary.
The data dictionary contains the name and description of each data element.
The data dictionary is a tool used exclusively by the database administrator.
What is the result of the following SQL statement ?
SELECT A.emp_Name, B.ph_num
FROM emp A LEFT OUTER JOIN phone B
ON A. emp_ID = B.emp_ID
A list of employees phone number
A list of all employees that have spouses, with phone number included in the list
A list of all employees names, including the phone number if they have one
Two lists : One list of employees, the other of phone numbers
Select the incorrect statement
BCNF is stronger than 3NF
Relational algebra is a non-procedural language
Every conflict serializable schedule is view serializable.
none of the above
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
The language used in application programs to request data from the DBMS is referred to as the
DML
DDL
VDL
SDL
.................. 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
Symbol to represent weak entity set in ER Model
Dotted rectangle
Square
Doubly outlined rectangle
Diamond
In an Entity-Relationship Diagram Diamonds represents
Attributes
Multi-valued attributes
Weak entity set
Relationship sets
The mode in which data item may be locked
Partner
Mutual
Exclusive
Atomic
Which of the following produces the relation that has attributes of R1 and R2
Cartesian product
Difference
Intersection
Product
Encoding method which does not provide for synchronization
B8ZS
Manchester
RZ
NRZ-L
The overall design of a database is called
Subschema of the database
Schema of the database
Structure of the database
View of the database
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
The ability to modify the conceptual schema without causing any change to the application program is known as
Physical data independence
Logical data independence
External data independence
Static data
A DBMS query language is designed to
support end users who use English-like commands.
support in the development of complex applications software.
specify the structure of a database.
all of the above.
In an E-R diagram attributes are represented by
rectangle.
square.
ellipse.
triangle.
DBMS helps achieve
Data independence
Centralized control of data
Neither A) nor B)
both A) and B)
EEPROM
Electrically Extractable Programmable Read Only Memory
Electrically Erasable Programmable Read Only Memory
Electronically Erasable Programmable Read Only Memory
Electrically Erasable Programmable Read Only Memory
The method of access which uses key transformation is known as
direct.
hash.
random.
sequential.