SQL Normalization

AbhishekBiswas

@abhishekbiswas-XPBTe5 • Oct 25, 2024

Oct 25, 2024

989

Can somebody help to get a clear concept of SQL Normalization .

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PraveenKumar Purushothaman

@praveenkumar-66Ze92 • Apr 28, 2012

Check out this video. It is very easy to understand and the concept is explained well using MS SQL Server... 😀
Ankita Katdare

@abrakadabra • Apr 28, 2012

AbhishekBiswas
Can somebody help to get a clear concept of SQL Normalization .
Yeah sure. Where are you stuck at? I mean what part you did not understand? I can help.
AbhishekBiswas

@abhishekbiswas-XPBTe5 • Apr 28, 2012

AbraKaDabra
Yeah sure. Where are you stuck at? I mean what part you did not understand? I can help.
infact could you guide me a lil , ,i gt a very lil knlege in this . Thanks in adv.
PraveenKumar Purushothaman

@praveenkumar-66Ze92 • Apr 28, 2012

AbraKaDabra
Yeah sure. Where are you stuck at? I mean what part you did not understand? I can help.
AbhishekBiswas
infact could you guide me a lil , ,i gt a very lil knlege in this . Thanks in adv.
Did you people see the video posted by me? 😛
Ankita Katdare

@abrakadabra • Apr 28, 2012

#-Link-Snipped-# Yup. The video covers everything.

I wanted to ask if he wants to share a query for which he is trying normalization, so that we can help him out.
PraveenKumar Purushothaman

@praveenkumar-66Ze92 • Apr 29, 2012

AbraKaDabra
#-Link-Snipped-# Yup. The video covers everything.

I wanted to ask if he wants to share a query for which he is trying normalization, so that we can help him out.
Awesome!!! Sorry, I misunderstood... Great, AKD... 😀
Prashant Munshi

@prashant-munshi-qp7Wu5 • Apr 29, 2012

SQL Normalization is a term not heard of. SQL is a language used for accessing Relational Databases, the language is non-procedural, statement like, that we use in real life. Normalization is a process in a database to create such tables (called relations) which only represent a set of particular type of entity in the database. The process entails gathering the attributes only relevant to the information for a particular type of entity. For example, if I want to maintain the data about students who are offered training in some discreet subjects in IT and create a table having columns - student id, subject, fees, phone num - then such table would not be appropriate as per principles of RDBMS, since such tables contain the data about the students and subjects as well (2 types of entities). So when we apply principles of normalization here, then the table would be first split into two - student id, phone, subject and another table subject, fees. Since in this fees is relevant to subject (so is subject information) and phone is relevant to student id (so is students' information). The splitting is based on a concept of dependency which has arithmetic base and for more info, if allowed on this site, may I redirect you to : #-Link-Snipped-#
Prasad Ajinkya

@prasad-aSUfhP • May 5, 2012

Hey, I also found this very simple and well explained article - #-Link-Snipped-#
Prashant Munshi

@prashant-munshi-qp7Wu5 • May 6, 2012

kidakaka
Hey, I also found this very simple and well explained article - #-Link-Snipped-#
I have gone through this article/blogpost. A great article indeed. But here I am reproducing a line from this post. "Database normalisation is the process of arranging the layout of a database's fields and tables with the aim of minimising dependency and redundancy."
The underlined and emboldened part "minimizing dependency" is quite not a heard of term. Technically there is no action such as "minimization" of dependency. There are three types of dependencies - Functional, Partial and Transitive. Of the three a relation is said to be well structured with the functional dependency, while other two types of dependencies, if present, then they give rise to insert, update, delete anomalies and data redundancy, hence undesirable. Of course partial dependency CAN only exists in cases if the relation has composite primary key. Transitive dependency is observed when a non-key has functional dependency on another non-key attribute. Decomposition (splitting) of the table with the aim to separate out those dependent columns along with their keys (columns on which they depend) is part of the process of normalization but I have some reservation about the use of emboldened term in the definition of Normalization.
AbhishekBiswas

@abhishekbiswas-XPBTe5 • May 6, 2012

Following ... thanks for all supports😀