Database Normalization
Here we will discuss four types of Normalization and some important concepts like candidate keys , Prime & Non-Prime attributes Database Normalization is a technique to remove or reduce redundancy from the tables in the database. Types of Redundancy There are two types of redundancies that can occur in database tables. Row Level Redundancy In this type of redundancy, there is a repetition of the same row in the same table. For example, a table name as 'STUDENT' in which data of students is entered, if we enter the same student's data multiple time then, in this case, Row Level redundancy occurs as shown below: In the above case, there is a repetition of a student data whose name is 'Haider', this is what we called row-level redundancy. The solution of Row Level Redundandancy This Row-level Redundancy can be corrected by setting a primary column in the table. In this case, we set SID as the primary key column ( such column must contain unique & not null
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