NORMAL FORMS
CONTENT
- Database Normalization
- Purpose for Normalization
- Problem Without Normalization
- Data Anomalies
- Normalization Rules
Database Normalization
Database Normalization is a technique for organizing the data in the database. Normalization is a systematic approach to decomposing tables to eliminate data redundancy and undesirable characteristics like Insertion, Update and Deletion anomalies. It is a multi-step process that puts data into tabular form by removing duplicated data from the relation tables.
Purpose for Normalization
Normalization is used for mainly two purposes:
- Eliminating redundant (useless) data.
- Ensuring data dependencies make sense i.e data is logically stored.
Problem Without Normalization
Without Normalization, it becomes difficult to handle and update the database, without facing data loss. Insertion, Updation and Deletion anomalies are very frequent if the Database is not Normalized. To understand these anomalies let us take an example of the Student table below.
Data Anomalies
A database anomaly is a fault in a database that usually emerges as a result of shoddy planning and storing everything in a flat database.
- NEW: Download the entire term's content in MS Word document format (1-year plan only)
- The complete lesson note and evaluation questions for this topic
- The complete lessons for the subject and class (First Term, Second Term & Third Term)
- Media-rich, interactive and gamified content
- End-of-lesson objective questions with detailed explanations to force mastery of content
- Simulated termly preparatory examination questions
- Discussion boards on all lessons and subjects
- Guaranteed learning