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Normalization

InstitutionAffiliation

denotes the organization of data in an efficient way in a database. Agood database is characterized by normalized data. Minimization ofredundancy and maintaining data dependency is fostered when data isnormalized in a database (Yan, 2010). In addition, normalization ofdata takes into perspective breaking down large tables into smallerand easily understood tables. Further, in a bid to attain accuratepresentations it is prudent to focus on normalization as itencourages accurate data presentations and constraints. At the sametime, normalization aids conducting of a series of tests on relationsto establish whether a database system meets the normal requirements(Czenky, 2014). Essentially, the main reason for normalization is toprevent possible data corruption that occurs during insertion,deletion or update of data in a database. Normally, a database isnormalized after logical modeling but prior to the physical phase ofdatabase design.

FirstNormal Form

Thefirst normal form in a database is attained when there are norepeating groups in the table. An example in a school set up can bedepicted by an ERD database of books that are rented out to students.The database contains Customer ID, Full Names, Book Rented andAddress. The table below shows a typical example of data in FirstNormal Form:

Customer_ID

Full_Names

Books_Rented

Address

001

Mathew Mark

Introduction to IT, Management Science

076 NY

002

Margret Mayo

Introduction to Accounting, English Literature

786 WDC

Table1: First Normal Form

Fromthe table it can be noted that Books Rented is a multi valuedattribute since a single customer can take multiple books. Thus, inorder for the table to be in its first normal form, each filed oughtto contain a single value. Thus, the above table can be expressed inits first normal form as depicted below:

Customer_ID

Full_Names

Books_Rented

Address

001

Mathew Mark

Introduction to IT

076 NY

001

Mathew Mark

Management Science

076 NY

002

Margret Mayo

Introduction to Accounting

786 WDC

002

Margret Mayo

English Literature

786 WDC

Table2: First Normal Form

SecondNormal Form

Asecond normal form in a database table is achieved if a table is inits first normal form and all the non-prime attributes are equallyfunctional fully on the dependent key attributes (Demba, 2013). Thetable above which is in its first normal form can be split into thefollowing tables

Customer_ID

Full_Names

Address

001

Mathew Mark

076 NY

002

Margret Mayo

786 WDC

Table3: Second Normal Form

Customer_ID

Books_Rented

001

Introduction to IT

001

Management Science

002

Introduction to Accounting

002

English Literature

Table4: second Normal Form

Tablethree is depicted in its second normal form since every non keyattribute (Address and Full_Names) is fully functional on thedependent key attribute which is the Customer_ID. Table four is alsoillustrated in its second normal form since it forms a composite keyof customer ID and Books Rented that aids in identification of therows uniquely.

ThirdNormal Form

Atable in a database can be said to be in its third normal form if itis in its second normal form and has no transitive dependency (Wang,Du, &amp Lehmann, 2010). Transitive dependency is exhibited whenchanging a non key attribute causes a change in the some othernon-key attribute. Table three and four so far follow the rules of athird normal form since there is no transitive dependency exhibited.

De-normalization

De-normalizationis required when tables in a database get huge after splitting andmade into normalized tables. Thus, in this case data may be requiredto be collected or manipulated from multiple tables and compellingthe use of SQL queries with so many JOINS that lead to slowprocessing and response time (Duggal, Srivastav, &amp Kaur, 2014).There is no doubt that business rules would impact both normalizationand de-normalization by confusing the meanings of terms that may beused in a database. It is prudent to ensure that the business rulesare written in simple and plain language to enhance comprehension.The rules within a de-normalized engine ought to be tested anddefined.

Inconclusion, normalization is adopted in databases in a bid to reduceredundancies. Existence of redundancies impacts reliability andefficiency in databases, thus, the need to constantly rely onnormalization. is a multi-step process and oftenrequires keenness to undertake appropriately. However, when tablesget huge it is imperative to de-normalize the data for easiermanipulation purposes.

References

Czenky,M. (2014). The Efficiency Examination of Teaching of Different Methods.International Journal of Database Management Systems,&nbsp6(2),1-18. http://dx.doi.org/10.5121/ijdms.2014.6201

Demba,M. (2013). Algorithm for Relational Database Up to3NF.&nbspInternationalJournal of Database Management Systems,&nbsp5(3),39-51. http://dx.doi.org/10.5121/ijdms.2013.5303

Duggal,K., Srivastav, A., &amp Kaur, S. (2014). Gamified Approach toDatabase .International Journal of Computer Applications,&nbsp93(4),47-53. http://dx.doi.org/10.5120/16207-5505

Wang,T., Du, H., &amp Lehmann, C. (2010). Accounting For the Benefits ofDatabase . AJBE,&nbsp3(1).http://dx.doi.org/10.19030/ajbe.v3i1.371

Yan,B. (2010). Formulas of Retrieval Rate in Database Based on Design.&nbspCIS,&nbsp2(3).http://dx.doi.org/10.5539/cis.v2n3p32