What is normalization and what are the different forms of
normalizations?
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Answer / swapna
Normalization is the process of efficiently organizing data
in a database. There are two goals of the normalization
process: eliminate redundant data (for example, storing the
same data in more than one table) and ensure data
dependencies make sense (only storing related data in a
table). Both of these are worthy goals as they reduce the
amount of space a database consumes and ensure that data is
logically stored.
First normal form (1NF) sets the very basic rules for an
organized database:
? Eliminate duplicative columns from the same table.
? Create separate tables for each group of related data and
identify each row with a unique column or set of columns
(the primary key).
Second normal form (2NF) further addresses the concept of
removing duplicative data:
? Meet all the requirements of the first normal form.
? Remove subsets of data that apply to multiple rows of a
table and place them in separate tables.
? Create relationships between these new tables and their
predecessors through the use of foreign keys.
Third normal form (3NF) goes one large step further:
? Meet all the requirements of the second normal form.
? Remove columns that are not dependent upon the primary
key.
Finally, fourth normal form (4NF) has one additional
requirement:
? Meet all the requirements of the third normal form.
? A relation is in 4NF if it has no multi-valued
dependencies
Is This Answer Correct ? | 28 Yes | 3 No |
Answer / asif nadeem
Normalization is simply a process which is use to store
data efficiently on data base but in this it is
underestimated rules that must be performed.
1) Delete the data which repeating again and again
2) Maintain data of rows and columns into their releated
tables and columns.
there are some types of Normalization
1) 1N
2) 2N
3) 3N
4) 4N
1N:it is known as first normalization and in thsi we
transfer data towards the releated columns and subsets in
which data is repeating is deleated
2N:in this form the 1N steps are implimented and after it
data is maintain in the same table and in columns
3N:in this 2N steps are performed and the subsets of
predcessors are deletd or they are arranged into the
different but of same tables, releation ship is built b/w
the data so that it can be easily accessable.
4N:in this type the 3N steps are performed and main thing
which extra in this is no repeated is present in the 4N
Is This Answer Correct ? | 3 Yes | 1 No |
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