Normalization

Normalization is the process of rearranging the fields and tables of a relational database to reduce data redundancy and dependency.

Normalization typically consists of splitting up big tables into smaller sized (and fewer redundant) tables along with characterizing relationships between them. The objective would be to separate data to ensure that additions, deletions and alterations to a field can be made in only one table and then propagated throughout the remainder of the database through defined relationships.

Data Redundancy

Data mustn’t be redundant, meaning that the duplication of data ought to be kept as small as possible for a variety of reasons. By way of an example, it is unnecessary to store an individual’s address in more than a single table. With replicated data, unneeded space is utilized. Confusion is invariably a hazard whenever, for example, an address for a staff member in one table doesn’t match up with the address of the same worker in another table. Which table is correct? Do you have records to verify the member of staff’s current address? Just as if data supervision wasn’t difficult enough, redundancy of data could prove to be a disaster.

Normal forms

A system of acquiring the above desired goals exists. The idea is to deconstruct data working with “normal forms”.
You can find three key normal forms, each with rising stages of normalization:

-First Normal Form (1NF): Each individual field in the table holds distinct information. For example, in an employee list, every table would include only one birth date field.

-Second Normal Form (2NF): This indicates that no field should only be somewhat dependent upon any candidate key in the table. This does not simply include the primary key, but any field combinations that might exclusively identify a row.

-Third Normal Form (3NF): No replicated information is allowed. So, for instance, if two tables both need a date of birth field, the date of birth data could be split up into a separate table, and the two other tables would then get the date of birth information via an index field for the date of birth table. Any change to a date of birth would be mirrored in every table that links to the date of birth table.

Advantages of Normalization

Normalization offers countless benefits to a database. A lot of the important rewards are the following :

• Elimination of redundant data
• Data uniformity throughout the database
• A much better grip on database stability
• Greater general database organization
• A additional flexible database design

Organization is caused by the normalization approach, making everyone’s job more efficient, from your user who accesses tables to the database administrator (DBA) who’saccountable for the overall management of every item within the database. Data redundancy is minimized, which makes easier data structures and saves disk space. Due to the fact that duplicate data is lessened, the chance of not consistent data is significantly diminished. It is much more efficient to modify a smaller table than to adjust one significant table that retains each of the essential data within. Lastly, protection is provided in the sense that the DBA can grant usage of limited tables to particular users. Security is a lot easier to regulate when normalization has happened.
Data integrity is the assurance of consistent and accurate data within a database.

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