What is normalization

Question

Hello Everyone I am beginner to the database mangement system just started learning I want to learn about the Normalization and what are the purposes of normalizationAdvantages and disadvantages of it

Daniel Jones · Answer

Normalization is the process of efficiently organizing data in a database. There are two goals of the normalization process: eliminating redundant data and ensuring data dependencies make sense. Advantages Smaller database: By eliminating duplicate data Better performance Disadvantages Tables contain codes instead of real data Data model is difficult to query against

Krishna Rajput Singh · Answer

Hello Thank you for writing below answer will be helpful for you What is Normalization Normalization is the procedure to split the relation into relations with less attributes thereby minimizing the redundancy of the data and minimizing the insertions deletions and updating. In other words we can say that the normalization is that process in which we renovate an un-normalized relation into relations. There is a sequence of stages or steps on which the normalization works. This sequence is called normal forms. The normal forms are relevant to entity relations. If the form satisfies a certain sets of constraints then a table or a relation comes to the particular normal form. There are above five normal forms. These are 1NF 2NF 3NF 4NF and 5NF. Here NF stands Normal Form. It is very important for relational data model to consider that the first normal form (1NF) is very grave in creating the relations. Rests of all the forms are optional. There are some guidelines which help to create a good database. There is always a need for updating the database so that there are three anomalies for data modification. Insert–This irregularity refers to the circumstances when one cannot insert a new row(tuple) into a relation because of the shortage of data. Delete-The delete anomaly refers to a state of affairs where the removal of records outcome in accidental loss of several other significant data. Update-The update abnormality is a state wherever an update of a lone data value needs numerous rows of data to be updated. Advantages and Disadvantages of normalization Advantages of normalization are as follows- Reduce the redundancy. A large amount added bendable database design. Better overall database association. Data uniformity inside the database. With these advantages there are some disadvantages of normalization given below- You are not able to begin construction of database prior to know what the customer desires. With the increase in the normal forms its performance gets slower and slower. It is extremely time consuming and complicated method in normalizing relations of advanced degree. Careless disintegration may guide to terrible design of database which may lead to somber troubles. Types of Normalization There is a series of normal forms but the most commonly used normal forms are 1NF 2NF and 3NF given below. First normal form(1NF)-In 1NF the column must have unique value because the repeating group of data cannot exist in arrow that containing the data. Each row of data must have an identifier to identify the data i.e primary key. For example in a student named table the name is repeated again and again of the same id it makes the table very long and complex. To reduce those tables to the first normal form break the table into two parts where the marks and names by id are given separately in table. Second normal form(2NF)-A table to become normalized to the Second normal form(2NF) should gather all the stuff of first normal form and there have to not be any fractional need of the column on primary key. It means a table that has concatenated primary key every column in the table that is not part of the primary key must depend upon the whole concatenated key for its maintenance. So if any column depends only on one part of the concatenated key then the table gets fails. Third Normal form(3NF)-It applies that all non-prime attribute of table must be reliant on primary key. The transitive functional dependency should be detached from the table. The table must be in Second Normal form. The benefits of detaching the transitive dependence are that the quantity of the duplicate data is decreased and the data integrity can be accomplish. if find helpful answer mark as correct answer...

Ramesh Palanivel · Answer

Hi Arul Try this URL they explained very clearly what is normalization... It will ve very easy to under.... http://beginnersbook.com/2015/05/normalization-in-dbms/

Nitin Sontakke · Answer

Furthermore if you just google what is normalization (which I just did) you will get several hundred hits which explain the concept in great amount of detail. I am sure that would be lot more helpful to you than anyone of us telling you. This is because we are not professional trainers here.

Nilesh Shah · Answer

If you are/were a student in a computer related field I'm sure you have studied the concept of database normalization. I don't know what specific you want to ask us here in this forum apart from the google search results you can get it on your own. Otherwise your question belongs more to interviews section and not here.