Which of the following normal forms will you use to represent these relationships in the tables?

You work as a Database Administrator for Dowtech Inc. A table named StudentInformation exists in a
database. The table has columns named student_names, student_marks, and student_courses. Some
students who have opted for various courses have got different marks in them. This implies that the table has
two many-to-many relationships. You have to ensure that these two relationships are not represented ina
single table and that the student_name column exists in both tables. Which of the following normal forms will
you use to represent these relationships in the tables?

You work as a Database Administrator for Dowtech Inc. A table named StudentInformation exists in a
database. The table has columns named student_names, student_marks, and student_courses. Some
students who have opted for various courses have got different marks in them. This implies that the table has
two many-to-many relationships. You have to ensure that these two relationships are not represented ina
single table and that the student_name column exists in both tables. Which of the following normal forms will
you use to represent these relationships in the tables?

A.
4 NF
SQL

B.
3 NF
QL

C.
2 NF
DDL

D.
1 NF
XML

S.
QUESTION 70
Which of the following is an ANSI approved languagefor communicating and managing data in a relational
database management system (RDBMS)?

A.
4 NF
SQL

B.
3 NF
QL

C.
2 NF
DDL

D.
1 NF
XML

Explanation:
Fourth normal form (4NF) is a normal form used in database normalization. Introduced by Ronald Fagin in
1977, 4NF is the next level of
normalization after Boyce-Codd normal form (BCNF). Whereas the second, third, and Boyce-Codd normal
forms are concerned with functional
dependencies, 4NF is concerned with a more general type of dependency known as a multivalued
dependency. Symbolically, it can be
represented as follows:
If A -> > B|C, then A -> B and A -> C
Here, A, B, and C are attributes.
Answer D is incorrect. First normal form exists when all the columns in a table are atomic i.e., only a single
value is allowed in each
column. Also, there should not be a group value like more than one phone number in a phone number column.
If a table violates the first
normal rule, following steps should be taken to normalize the database:
To make column atomic, divide them into multiple columns. If there is group value, create separate tables for
the column and relate new table with a foreign key.Answer C is incorrect. Second normal form (2NF) isused in
database normalization. A table that is in first normal form must meet
additional criteria if it is to qualify for second normal form. Specifically, a 1NF table is in 2NF ifand only if, given
any candidate key and any
attribute that is not a constituent of a candidate key, the non-key attribute depends upon the whole of the
candidate key rather than just a
part of it.
Answer B is incorrect. Third normal form (3NF) is used in database normalization. A table is in 3NF ifand only
if the relation S (table) is
in second normal form (2NF) and every non-prime attribute of S is non-transitively dependent on every key of

Structured Query Language (SQL) is used to communicate and manage data in a relational database
management system (RDBMS).
Structured Query Language (SQL) is the most common language used to access relational databases.
SQL was developed by IBM in the
1970’s, and SQL version 3 was officially defined bythe American National Standards Institute (ANSI).
Most DBMS’s conform to the ANSI SQL-92
standard. It is a nonprocedural language and supports many database systems that are in use today, such as
MySQL, PostgreSQL, Berkeley
DB, Oracle, DB2, Sybase, Informix, Microsoft SQL, etc. Answer C is incorrect. Data Definition Language(DDL)
is a part of SQL that allows a user to create objects (such as tables, stored
procedures, indexes, and triggers) within a database. It also allows a user to delete already created objects.
Answer B is incorrect. Query Language (QL) is a setof commands used to retrieve, modify, and update data
from the database; it is a
language for formulating queries for a given dataset.
Answer D is incorrect. Extensible Markup Language (XML) is a general-purpose specification for creating
custom markup languages. It is
classified as an extensible language because it allows the user to define the mark-up elements. It is used to aid
information systems in
sharing structured data, especially via the Internet, to encode documents, and to serialize data. XML is
recommended by the World Wide Web
Consortium (W3C). It is a fee-free open standard. The recommendation specifies lexical grammar and parsing
requirements.



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warren

warren

4NF is concerned with a more general type of dependency known as a multivalued
dependency. Symbolically, it can be
represented as follows:
If A -> > B|C, then A -> B and A -> C

Olivia

Olivia

How is this 4NF?