From 30ee3488e293c34d6cc7ee04de0137728bcb90a9 Mon Sep 17 00:00:00 2001 From: SoundDrill31 <84176052+sounddrill31@users.noreply.github.com> Date: Wed, 25 Dec 2024 17:14:56 +0530 Subject: [PATCH] BCA: DB: Finish Unit 4 --- .../BCA/3rdsem/dbms/solved/faculty-given.md | 39 ++++++++++++++----- 1 file changed, 30 insertions(+), 9 deletions(-) diff --git a/NEP2020/2024/BCA/3rdsem/dbms/solved/faculty-given.md b/NEP2020/2024/BCA/3rdsem/dbms/solved/faculty-given.md index 73d614c..a8d0967 100644 --- a/NEP2020/2024/BCA/3rdsem/dbms/solved/faculty-given.md +++ b/NEP2020/2024/BCA/3rdsem/dbms/solved/faculty-given.md @@ -128,7 +128,7 @@ ER Notations are used to represent various components of the ER Model, using dif A Relationship in a Database refers to a connection between properties of tables. - It is a logical association between different entities stored in seperate tables - Eg. Customers, Products, and Orders are linked to each other using relations - +TODO: Finish # Unit 3: ## Q1. What is a Domain, Attribute and Tuple? @@ -459,14 +459,35 @@ There are Two Types of Functional Dependencies: - i.e. If X → Y and Y is not a subset of X, then it is called Non-trivial functional dependency. [GeeksForGeeks](https://www.geeksforgeeks.org/types-of-functional-dependencies-in-dbms/) -## Q4. 1st normal Form -TODO: Solve -## Q5. 2nd normal Form -TODO: Solve -## Q6. 3rd normal form -TODO: Solve -## Q7. BCNF -TODO: Solve +## Q4. 1st normal Form, 2nd normal Form, 3rd normal form, BCNF +Normalization is the process of minimizing redundancy from a relation or set of relations. +- Redundancy in relation may cause insertion, deletion, and update anomalies. + - So, it helps to minimize the redundancy in relations. + - Normal forms are used to eliminate or reduce redundancy in database tables. +- What normalization basically does is ensure that your data is free of data redundancy or duplicate data and does not have data anomalies that would otherwise compromise its integrity. + +Levels of Normalization: +- ***First Normal Form*** (1NF) +- ***Second Normal Form*** (2NF) +- ***Third Normal Form*** (3NF) +- ***Boyce-Codd Normal Form*** (BCNF) + +Explanation: +- First Normal Form (1NF): + - This is the most basic level of normalization. + - In 1NF, each table cell should contain only a single value, and each column should have a unique name. The first normal form helps to eliminate duplicate data and simplify queries. +- Second Normal Form (2NF): + - 2NF eliminates redundant data by requiring that each non-key attribute be dependent on the primary key. + - This means that each column should be directly related to the primary key, and not to other columns. +- Third Normal Form (3NF): + - 3NF builds on 2NF by requiring that all non-key attributes are independent of each other. + - This means that each column should be directly related to the primary key, and not to any other columns in the same table. +- Boyce-Codd Normal Form (BCNF): + - BCNF is a stricter form of 3NF that ensures that each determinant in a table is a candidate key. + - In other words, BCNF ensures that each non-key attribute is dependent only on the candidate key. + +[(GeeksForGeeks, Explanation)](https://www.geeksforgeeks.org/normal-forms-in-dbms/) +[(GeeksForGeeks, Forms)](https://www.geeksforgeeks.org/normal-forms-in-dbms/) # Unit 5: ## Q1. Transaction states