Which of the following Key is used to represent relationship between the tables?
Primary key
Secondary Key
Foreign Key
None of these
Correct Answer :
C. Foreign Key
Related Questions
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
The syntax to select all column from the table is
select all from tablename
select * from tablename
select from tablename
none of these
The index table has …… Columns.
1
2
3
4
A fragmentation is categorized in
1 part
2 part
3 part
4 part
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
An entity set that does not have sufficient attributes to form a primary key is a
strong entity set.
weak entity set.
simple entity set.
primary entity set.
Extended Entity Relationship model consists of which of the following
i) Specialization
ii) Generalization
iii) Categorization
i and ii only
ii and iii only
i and iii only
All i, ii iii
Which one of the following is provided by a data dictionary ?
User data
Database structure data
Sorted data
Functional data
The left outer join takes all tuples
in the left relation which didnt match with any tuple in right relation
in the left relation which matched with a tuple in right relation
in the right relation which didnt match with any tuple in left relation
in the right relation which matched with a tuple in left relation
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
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 union of primary keys of a related entity becomes …………. Of a relation.
primarykey
superkey
candidatekey
foreignkey
The statement in SQL which allows to change the definition of a table is
Select
Update
Create
Alter
B-Tree is used for
searching data
storing data
both A and B
none of these
Object based data models are used in describing the abstraction of the following levels?
Conceptual and view
Only physical
Physical and conceptual
Only conceptual
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
Transaction access data using two operations
read(), print()
read(), write()
scan(), write()
none of the above
Authorization command in SQL
Allow
Access
Grant
none of the above
Expand the acronym OLAP
Object Linked Access Program
Organizational Architecture Processing
Online Analytical Processing
none of these
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 mode in which data item may be locked
Partner
Mutual
Exclusive
Atomic
Natural mask for a Class A network
255.0.0.0
255.255.0.0
255.255.255.0
none of these
In an E-R diagram attributes are represented by
rectangle.
square.
ellipse.
triangle.
Select the incorrect statement(s)
i) Shared locks are compatible with each other.
ii) A relation which is in 3NF may have redundancy due to composite keys.
iii) A table in a database can have multiple indexes.
i only
ii, only
ii, iii only
none of the above
The output of the Data Definition Language is stored in the
view table
schema
metadata
all of the above.
QBE
Query By Execution
Query By Example
Query By Extraction
None of the above.
A composite attribute is converted to individual attributes in which of the following normal form ?
first
Second
third
fourth
Range variables are designed using the
TO clause
FROM clause
RANGE clause
none of the above
Relational Algebra is
Data Definition Language.
Data Manipulation Language
Procedural query Language
None of the above
The race condition occurs when
Two concurrent processes attempt to interact with each other.
Two concurrent processes interact with different data files.
Two concurrent processes attempt to hold a data item .
none of the above.