First Normal form in DBMS

Let’s study Database First(1st) Normal form and repeating groups.
What is the first normal form?
A relation/table is in the first normal form if it does not contains 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.

Example of first normal form

Roll No  Name Marks
1 Shahzeb 98
2 Basit 90
3 Sameed 44
2 Basit 70

Here, Roll No 2 is the repeating group because Roll number 2 is for only one instance of an entity student.

How to convert a table into the first normal form?

We will remove the repeating groups;

Roll No  Name Marks
1 Shahzeb 98
2 Basit 90
3 Sameed 44

Excercise 1NF to 5NF

Example: 1NF

Original Table
Emp_ID Name Language
1.     T4Tutorials A English
2.     T4Tutorials B English, Chinese
3.     T4Tutorials C Chinese
4.     T4Tutorials D English, German, Russian

FIRST NORMAL FORM

FIRST NORMAL FORM
Emp ID Name Language
1. T4Tutorials A English
2. T4Tutorials B English
2. T4Tutorials B Chinese
3. T4Tutorials C Chinese
4. T4Tutorials D English
4. T4Tutorials D German
4. T4Tutorials D Russian

Topic Covered

Database First(1st) Normal form and repeating groups.

normal forms in DBMS with examples.
normalization in the database with example tables.
normalization example.
first normal form SQL.
normalization in the DBMS ppt.

Read Tutorials about Normalization in DBMS

  1. First Normal form in DBMS
  2. Second normal form Examples in DBMS
  3. Third normal form
  4. Boyce-Codd Normal Form (3.5 NF)
  5. Fourth Normal Form
  6. Fifth Normal Form (5NF)