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

Answer Posted / 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.

Is This Answer Correct ?    21 Yes 2 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Write the advantages of partitioning a session?

745


Is it possible to revert a global repository to local one and why?

613


Explain Dataware house architecture .how data flow from intial to end?

2124


Briefly explain your complete project(sales) flow, (ie. from source received from client, transformations, then despatch to end user) what are all the process. Kindly give step by step process.

1847


Please tell me which institute is the best to study Informatica and asp.net in chennai Also please send me the latest interview questions in asp.net,c# and sql server to my id ramtryin@gmail.com

1588






If i have source as flat file. how can i store the header and trilor into one target and data into one more target. |------>target1(header+trailor) source------ |------>target2(data) can any one please help me

1553


lookup transformation with screenshots

3559


Mine is Insurance Domain, So interviewer asked about terms like underwriting, disbursement amt, Reinsurance

1590


What is Story point Estimation ? Can any one give just an introduction about this ? Advance Thanks

4783


What the difference is between a database, a data warehouse and a data mart?

597


What is a shortcut and copy in Informatica and how two are different with each other?

686


Where are the source flat files kept before running the session?

624


What is an aggregator transformation?

617


What is intricate mapping?

590


COL1,COL2 ABC,1 XYZ,2 HERE IN COL2 VALUES 1,2 NOT STSANDARD(IE MEANS NOT FIXED VALUES LIKE OTHER SOME VALUES LIKE 10,20) O/P IS COL1,COL2 ABC,2 XYZ,1

1533