# 4NF is designed to cope with____?

4NF is designed to cope with :
(a). Multi-valued dependency
(b). Join dependency
(c). Transitive dependency
(d). None of these

## What is Multi-valued dependency?

A multivalued dependency consists of at least two attributes that are dependent on a third attribute thatâ€™s why it always requires at least three attributes.

## Exercise:

### “The table is with more than one multi-valued dependency”. Solve the problem to ensure 4th normal form

 STUDENT HOBBY LANGUAGE 1 Cricket English 1 Painting Urdu 2 Cricket Hindi 2 Painting English

## Solution

 STUDENT HOBBY 1 Cricket 1 Painting 2 Singing

Table 1:Â Hobby table with just one multi-valued dependency

 STUDENT LANGUAGE 1 English 1 Urdu 2 Hindi

Table 2:Â Language table with just one multi-valued dependency

3NF is designed to cope with :
(a). Multi-valued dependency
(b). Join dependency
(c). Transitive dependency
(d). None of these

## What is Transitive dependency?

Transitive dependency means that aÂ non-prime attribute A( other than the candidate key) depends on another non-prime attribute B and that B is entirely dependent on the candidate key.

 SPECIALIZATION CODE SPECIALIZATION NAME COURSE CODE COURSE NAME 1 Computing A1 BATABASE 2 Development A2 C++ 3 Computing A3 OPERATING SYSTEM 4 Development A4 OOP

Â

 SPECIALIZATION CODE SPECIALIZATION NAME COURSE CODE 1 Computing A1 2 Development A2 3 Computing A3 4 Development A4

Â

 COURSE CODE COURSE NAME A1 BATABASE A2 C++

2NF is designed to cope with :
(a). Multi-valued dependency
(b). Partial Functional Dependency
(c). Transitive dependency
(d). None of these

## What is Partial Functional Dependency?

 Employee name skill Current work location Elizabeth Graphic designer Germany Elizabeth Database Germany Elizabeth Hand writing Germany Eva Typing speed United States Robert Fluent in English United States Robert Leadership United States Haroon Typing speed United States

After 2NF

 Employee name Current work location Elizabeth Germany Eva United States Robert United States Haroon United States Employee name skill Elizabeth Graphic designer Elizabeth Database Elizabeth Hand writing Eva Typing speed Robert Fluent in English Robert Leadership Haroon Typing speed

1NF is designed to cope with :
(a). Multi-valued dependency
(b). Partial Functional Dependency
(c). Transitive dependency
(d). Repeating groups

## What is a Repeating group?

A repeating group is a group of two or more rows/records for an instance of an entity.

 Roll NoÂ Name Marks 1 Robert 77 2 Basit 90 3 Elizabeth 44 2 Basit 70

After removing the repeating groups;

 Roll No Name Marks 1 Robert 77 2 Basit 90 3 Elizabeth 44