Answer / gtp

Denormalization is a technique to move from higher to lower
normal forms of database modeling in order to speed up
database access

Answer / sd

Denormalization is introcution of controlled redundancy in
the database.

Use denormalization generally to optimize performace of
select query. to minimize joins used in the query.

Answer / abarna(cts)

As the name indicates, denormalization is the reverse
process of normalization. It's the controlled introduction
of redundancy in to the database design. It helps improve
the query performance as the number of joins could be
reduced.

Answer / sivaraman (gasc)

Denormalization is the process of attempting to optimize
the performance of a database by adding redundant data or
by grouping data. In some cases, denormalization helps
cover up the inefficiencies inherent in relational database
software. A relational normalized database imposes a heavy
access load over physical storage of data even if it is
well tuned for high performance

Answer / niraj kumar

Industrial experience---->

Denormalization or Normalization both we use on databse so
that any one can filter as well as retrive the data from
the tabel easily.
Denormalization - As the name suggest it is a reverse
process of normalization, means we fill some redundant data
in table so that user can retrive easily.
But actualy we use the major functionality of normalization
of higher normal form(BCNF, 4TH NF ,5TH NF, DKNF) in lower
normal form (1st and 2nd) because higher normal forms are
so costly to use, thats why we use denormalization to
reduce the cost of normalization.

Answer / sandeepa rout

De-normalization is the process of attempting to optimize
the performance of a database by adding redundant data. It
is sometimes necessary because current DBMSs implement the
relational model poorly.


Only one valid reason exists for denormalizing a relational
design - to enhance performance. However, there are several
indicators which will help to identify systems and tables
which are potential denormalization candidates. These are:



* Many critical queries and reports exist which rely upon
data from more than one table. Often times these requests
need to be processed in an on-line environment.

* Repeating groups exist which need to be processed in a
group instead of individually.

* Many calculations need to be applied to one or many
columns before queries can be successfully answered.

* Tables need to be accessed in different ways by different
users during the same timeframe.

* Many large primary keys exist which are clumsy to query
and consume a large amount of DASD when carried as foreign
key columns in related tables.

* Certain columns are queried a large percentage of the
time. Consider 60% or greater to be a cautionary number
flagging denormalization as an option.

Answer / asim javaid iqbal sahi

Denormalization is a technique to move from top to bottom database normal forms in order to optimize the performance of database and or to increase access time of database.

Answer / dhirendra kumar

DENORMALIZATION IS A TECHNIQUE TO MOVE FROM HIGHER TO LOWER NORMAL FORM IN ORDER TO SPEED UP THE DATABASE ACCESS.WHEN WE WANT TO DERIVE PHYSICAL DATA MODEL FROM LOGICAL DATA WE USE DENORMALIZATION.

Answer / ravindra gaikwad

In computing, denormalization is the process of attempting
to optimise the read performance of a database by adding
redundant data or by grouping data.[1][2] In some cases,
denormalization is a means of addressing performance or
scalability in relational database software.

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