what is normalization? explain 1st NF, 2nd NF, 3rd NF



what is normalization? explain 1st NF, 2nd NF, 3rd NF..

Answer / rakesh

Data normalization is a process in which data attributes
within a data model are organized to increase the cohesion
of entity types. In other words, the goal of data
normalization is to reduce and even eliminate data
redundancy, an important consideration for application
developers because it is incredibly difficult to stores
objects in a relational database that maintains the same
information in several places.

Level
Rule

First normal form (1NF)
An entity type is in 1NF when it contains no repeating
groups of data.

Second normal form (2NF)
An entity type is in 2NF when it is in 1NF and when all of
its non-key attributes are fully dependent on its primary
key.

Third normal form (3NF)
An entity type is in 3NF when it is in 2NF and when all of
its attributes are directly dependent on the primary key.

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