What is normalization? Explain different levels of
normalization?

Answer Posted / a.mohan kumar

To avoid redundancy and to constructing an efficient
database we use normalization.its a concept which is used to
construct efficient database .the types of normalization are:
First Normal form (1NF): A relation is said to be in 1NF if
it has only single valued attributes, neither repeating nor
arrays are permitted.

Second Normal Form (2NF): A relation is said to be in 2NF if
it is in 1NF and every non key attribute is fully functional
dependent on the primary
key.

Third Normal Form (3NF): We say that a relation is in 3NF if
it is in 2NF and has no transitive dependencies.

Boyce-Codd Normal Form (BCNF): A relation is said to be in
BCNF if and only if every determinant in the relation is a
candidate key.

Fourth Normal Form (4NF): A relation is said to be in 4NF if
it is in BCNF and contains no multi valued attributes.

Fifth Normal Form (5NF): A relation is said to be in 5NF if
and only if every join dependency in relation is implied by
the candidate keys of relation.

Domain-Key Normal Form (DKNF): We say that a relation is in
DKNF if it is free of all modification anomalies. Insertion,
Deletion, and update anomalies come under modification
anomalies.
om Namasivaya.

Is This Answer Correct ?    41 Yes 7 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Explain the cube operator?

602


Explain what a database is?

613


Explain about network model?

589


What is DB Development software?

1616


Where is dbms used?

623






If a column is an image value type, how you can compare column values? How can you use this column in join clause?

592


What are the main phases of database development?

540


explain detail about ftp in datastage?

1814


Explain about relational operator join?

616


Explain about xml databases?

624


Why does this query return 0?

623


Explain about a primary key?

572


On friday, you issued several insert statements using query analyzer. You then verified the data had been correctly entered with a select statement on monday, your users report that the data is not there what happened?

567


How can you log an error to the server event log from a stored procedure?

559


In which table collections errors are stored.

1940