DBMS

Normalization In Dbms

normalization - Normalization In Dbms

Normalization

Normalization is a process to control the database records and manage the data records in simplest format. It allows to manage the relationship between the data element and entities normalization help to process to data records in the simplest format and allow for manipulation is to cover the data records into simplest formal and reduces the residency form the database records are easy updates, manipulation etc database allow us to manage the normalization with different method.

First normal form

1 NF explaination with example of Normalization
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It is the method that allows managing the database simplest format for manipulating the records. In this method, tables contain no repeated groups. The repeating columns of field present in the announced table are removed from the adjusting tables and store into other tables and create relational with the help of common field. When a table has no repeating records and there can be only value in existing row and columns.

Functional dependecies-> The entity attributes are depended together representing the relationship between the functional dependencies different between well design database and simple data design. It identifies the interrelationship among attributes of the entity represented by a relationship. A functional dependency is denoted by(Arrow Symbol->) between the entity and attributes.

Full function dependency->

It is of functional dependencies that identify all attributes of an entity are depended on a single attribute. The non-key attribute for identifies the functional dependency known as a full functional dependency.

Partial dependency->

It is functional dependencies that identify some non-key field depended on and another on a key attribute that is known as partial dependencies. It means some attributes depend on particular attribute another key depended on another field.

Transitive dependency->

It is a dependency that relates the entity with the help of attributes. An entity related to other entity and another related to next entity. When one non-key attribute depended on other non-key attributes that are known as a transitive dependency.

Multivalued dependency->

This dependency is managed by first normal form. In this dependencies, a value is depended on multiple values. It means a table has more than one values to represent. The dependencies. It is known as table dependencies.

Join dependency->

It is a dependency that allows representing functional dependencies or multiple value dependencies related feature. The entity together with the help of its attributes.

Second normal form

2nf with example
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This normal form allows managing the table into normal form. If these normal form non-key attributes are depended on the whole key it means each-each field in a table must depend upon the entire key. In this normalization, non-key attributes are depended on a key attribute or in the composite. This issue arises only for a composite key with multiple columns then divide the table into 2 parts for normalization where the keys are composite.

Third normal form

Normalization In Dbms

3 nf example in normalization
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The table is in the third if all the non-key attributes of all other non-key attributes. A relation in this normal form a depended as nonprimary attributes transitive dependencies. In this normalization table also divide into another part for managing the transitive dependencies.

BCNF(Boyce Codd normal form)

This normal form is the extension of third normal form but much more strict than third normal form. It is also used to manage the prime key dependencies of the table. A relation in third normal form is not necessary BCNF.

Forth normal form

Normalization In Dbms

In this normal form, the multi-value dependencies are managed. In this normal form, the Boyce Codd normal form(BCNF) introduced as an extension which includes the multivalued dependencies. In this normalization, we divide table on the use of multivalue as forth normal form.

Fifth normal form

Normalization In Dbms

A table that manages multivalued dependencies with the help of forth normalization. The attributes are dependent together on entity also dependent together on generalized multivalue dependencies lead to another normal form called PJMF(Project join normal form). The PJNF also is known as five normal form. The concept of PJNF is an extension of fourth normal form from definition when join dependencies are considered it mean normal form is we used to manage the join.

 

DKNF(Domain key normal form)

The process of normalization to manage the dependencies through normal form, it has been possible to define normal form into the additional type of independence and constraints. This normal form doesn’t manage data processing to manage dependencies and general form. The DJNF is not in term of functional dependencies but the key manages the attribute and constraint a relations key in this normal form. If every general constraint can be related with knowledge of the attribute involved in the schema. The data are already managed at the time of transition through key and constraints.

Denormalization

It is a process of attempting to optimize to read performing of the database by adding duplicate data process allow as to manage the database using a particular application and maintain the normalized process. This is basically used in reading the redundant data and addressing performs relation database software.

Normalization In Dbms

Normalization In Dbms

 

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Pulkit Wadhwa

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