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
Correct Answer :
C. i and iii only
Related Questions
View never contains derived columns.
True
False
Cant say
none
The output of the Data Definition Language is stored in the
view table
schema
metadata
all of the above.
The attribute that can be divided into other attributes is called
Simple Attribute
Composite Attribute
Multi-valued Attribute
Derived Attribute
The ________ states that a foreign key must either match a primary key value in another relation or it must be null.
entity integrity rule
referential integrity constraint
composite attribute
action assertion
DECLARE is a(an)
executable statement.
declarative statement.
Ordered file
none of the above
The degree of the table with 500 rows and 7 columns is
500
7
3500
none of these
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.
Which of the following is logical topology?
Bus
Ring
Star
None of these
DBMS utility which allows to reconstruct the correct state of database from the backup and history of transactions
Backup
Recovery
Grant
Troubleshooting
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.
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
The control of concurrent execution is left with the
operating system
controller unit of the kernel
concurrency control component of the database system
none
File organization that provides fast access to any arbitrary record
Hashed file
B-tree
Ordered file
Unordered file
The host part in a class A type of an IP address has
12 bits
16 bits
24 bits
28 bits
The mode in which data item may be locked
Partner
Mutual
Exclusive
Atomic
When all attributes in a relation tuple are not functionally dependent only on the key attribute. Which of the following normalization is needed?
first
second
third
fourth
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
Log into a computer across an internet
IMAP
TELNET
POP3
Infrared
Noisy channel has ……… .. types of protocols
two
three
four
none
A transaction is said to have terminated if it has
either committed or aborted
either partially committed or aborted
either committed or failed
none of these
Which of the following extracts its data from the result of an SQL SELECT statement.
View
Synonym
Sequence
Transaction
A relation is said to be in ………. If it doesnt contain partial dependency
1NF
2NF
3NF
BCNF
Which of the following is not a constraint on a single relation?
check
unique
not null
is duplicate
Which of the following is also known as Offline storage ?
primary storage
secondary storage
tertiary storage
none of the above
............... noise is caused by the random motion of the electrons in a wire and is avoidable.
Thermal
Intermodulation
Cross talk
Impulse
Select the correct statement
i) Aggregate functions work on a group of data and return a single value.
ii) ODBC connects the frontend with the database without considering its compatibility
iii) View definition cant be used at multiple places through with clause .
i and ii only
ii and iii only
i and iii only
i only
The minimal set of super key is called
Primary key
Secondary key
Candidate key
Foreign key
The method of access which uses key transformation is known as
direct.
hash.
random.
sequential.
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
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