Dependency preservation is not guaranteed in
BCNF
3NF
PJNF
DKNF
Correct Answer :
A. BCNF
Related Questions
Which of the following aggregate functions does not ignore nulls in its results?.
COUNT .
COUNT (*)
MAX
MIN
What is data integrity?
It is the data contained in database that is non redundant.
It is the data contained in database that is accurate and consistent.
It is the data contained in database that is secured.
It is the data contained in database that is shared.
Which of the following relational algebraic operations is not from set theory?
Union
Intersection
Cartesian Product
Select
Which of the following is not a consequence of non-normalized database?
Update Anomaly
Insertion Anomaly
Redundancy
Lost update problem
What are the desirable properties of a decomposition
Partition constraint.
Dependency preservation.
Redundancy.
Security.
The middleware databases in which the business rules act are applicable to _______ tier architectures
Single
Three
Two
None
A weak entity has an ______ dependency on its owner entity, which can be used for both ON UPDATE and ON DELETE.
Direct
Indirect
Existence
No
The ______ key of a relation is the attribute (column) or collection of attributes, which uniquely identify a given tuple.
Primary
Foreign
Candidate
Alternate
According to the levels of abstraction, the schema at the intermediate level is called
Logical schema.
Physical schema.
Subschema.
None of the above.
In an E-R diagram double lines indicate
Total participation.
Multiple participation.
Cardinality N.
None of the above.
The clause in SQL that specifies that the query result should be sorted in ascending or descending order based on the values of one or more columns is
View
Order by
Group by
Having
Which of the following is not comparison operator?
<>
<
=<
>=
Which of the following constitutes a basic set of operations for manipulating relational data?
Predicate calculus
Relational calculus
Relational algebra
SQL
Relationships among relationships can be represented in an-E-R model using
Aggregation
Association
Weak entity sets
Weak relationship sets
Processed data is called _____
Raw data
Source
Information
Useful data
Employees in a company are each assigned their own office, i.e. for each employee there exists a unique office and for each office there exists a unique employee; This statement is an example of ____ type of relation.
1:1
1: Many
Many: One
Many : Many
A logical schema
is the entire database
Describes how data is actually stored on disk.
is a standard way of organizing information into accessible parts.
All of the above
If the closure of an attribute set is the entire relation then the attribute set is a
superkey
candidate key
primary key
not a key
_____is a full form of SQL.
Standard query language
Sequential query language
Structured query language
Server side query language
A DBMS is a ____ user if at most one user can use the system and is mostly restricted to personal computer systems.
None
Multi
Single
Concurrent
Which of the following relational algebra operations do not require the participating tables to be union-compatible?
Union
Intersection
Difference
Join
A _____ is used to define overall design of the database
code
data definition language
application program
schema
Which of the following is a reason to model data?
Understand each user's perspective of data
Understand the data itself irrespective of the physical representation
Understand the use of data across application areas
All of the above
For correct behaviour during recovery, undo and redo operation must be
Commutative
Associative
idempotent
distributive
______is a preferred method for enforcing data integrity
Constraints
Triggers
Stored procedure
Cursors
Relational Algebra is
Data Definition Language .
Meta Language
Procedural query Language
None of the above
E-R Modeling is achieved by using ____ diagrams
DFD
Flowcharts
Gantt Charts
E-R
A list consists of last names, first names, addresses and pin codes. If all people in the list have the same last name and same pin code a useful key would be
the pin code
the last name
the compound key first name and last name
Tr from next page
The ____ operator joins two or more conditions and displays rows only if that rows data satisfies all conditions specified.
OR
AND
NOT
ALL
The language that requires a user to specify the data to be retrieved without specifying exactly how to get it is
Procedural DML.
Non-Procedural DML.
Procedural DDL.
Non-Procedural DDL.