Database Management System (DBMS) 🎓

Introduction

• Purpose: Complete DBMS overview designed for semester exams
• Content: Important topics from university syllabi for DBMS
• Promise: 95% syllabus coverage, professional notes linked in the description, free access
• Format: Chapter-wise breakdown for easy navigation

Syllabus Coverage

1. Data and Information
   • Data: Raw facts and figures about an entity
   • Information: Processed data that is meaningful
   • Example: Data becomes information when analyzed in context
2. Database
   • Structured collection of data
   • Use of tables to store data in text format
   • Supports easy access, management, and updates
3. DBMS Definition
   • Software for efficient data storage, retrieval, and management
   • Ensures data safety, integrity, and concurrency control
4. File System vs. DBMS
   • Problems: Slow retrieval, data isolation, integrity issues, concurrency issues
   • DBMS advantages: Efficiency in large volumes, data management, querying, and reporting

Types of Database Systems

1. Commercial: Used in business sectors (e.g., CRM systems)
2. Multimedia: Handles audio, video, images (e.g., YouTube)
3. Deductive: Uses logical programming (e.g., Adobe Experience Manager)
4. Temporal: Time-based data (e.g., stock markets)
5. Graphical: Geographical information systems (e.g., Google Maps)

Database Management Terms

1. Instance and Schema
   • Schema: Structure of the database
   • Instance: Data at a particular time
2. ER Diagram
   • Tools for database representation
   • Entities, Attributes, and Relationships

Relational Model

1. Relational Database Management System (RDBMS)
   • Use of tables to store data
2. Normalization
   • Process of organizing data to reduce redundancy and improve integrity
   • Normal Forms: 1NF, 2NF, 3NF, BCNF
3. Functional Dependency
   • A relationship that exists when one attribute uniquely determines another attribute
   • Key concept in normalization

SQL (Structured Query Language)

1. DDL (Data Definition Language)
   • Commands: CREATE, ALTER, DROP, TRUNCATE
2. DML (Data Manipulation Language)
   • Commands: SELECT, INSERT, UPDATE, DELETE
3. DCL (Data Control Language)
   • Commands: GRANT, REVOKE
4. TCL (Transaction Control Language)
   • Commands: COMMIT, ROLLBACK, SAVEPOINT
5. Query Language
   • SELECT-FROM-WHERE clause explained
   • Advanced clauses: GROUP BY, HAVING, ORDER BY

ER Models and Diagrams

1. Entities: Strong and Weak entities
2. Attributes: Simple, Composite, Multi-valued, Derived
3. Relationships: One-to-One, One-to-Many, Many-to-Many, Self-referencing
4. Diagrams: ER Diagrams by Peter Chen, Use of rectangles, ellipses, diamonds

Indexing

1. Types of Index
   • Primary Index: Defined on primary key
   • Secondary Index: Defined on non-key attributes
   • Clustered Index: Defined on ordered data
2. Importance: Speeds up retrieval, reduces access time

Transaction and Concurrency Control

1. Transaction States: Active, Partially Committed, Committed, Failed, Aborted
2. Properties (ACID): Atomicity, Consistency, Isolation, Durability
3. Scheduling: Serial, Non-serial, Conflict Serializability, View Serializability
   • Techniques: Conflict graphs, precedence graphs
4. Concurrency Control
   • Lock-based: Shared and Exclusive locks, Two-Phase Locking (2PL)
   • Timestamp ordering
   • Validation-based

Database Recovery

1. Recovery Techniques
   • Log-based recovery: Immediate and Deferred database modification
   • Shadow paging
2. Types of Recovery
   • Transaction failure
   • System failure: Ensuring durability and consistency

Miscellaneous

1. Views, Sequences: Utility and management
2. Triggers and Procedures: Automated operations on databases
3. Cursors: Used for traversal of records in a database

Conclusion: Understanding DBMS and its components thoroughly prepares you for exams and practical applications in the real world. Make use of practice exercises and linked notes for deeper insight. Happy studying!