What you will learn

• SQL
• Normalization
• ER diagrams
• Transactions
• Indexing

Course content (28 lessons)

1. Unit 1: Comprehensive Overview of DBMS — 1.1 What is a Database Management System? A Database Management System (DBMS) is a complex software system that enables users to define, create, maintain, and control access to…
2. Unit 1: Characteristics of the Database Approach — 2.1 Self-Describing Nature of a Database System Unlike traditional file systems, a database doesn't just contain the data itself; it also contains a complete definition or…
3. Unit 1: DBMS Architecture - The Three-Schema Model — 3.1 The Three-Schema Architecture Also known as the ANSI/SPARC Architecture , its primary goal is to separate the user applications from the physical database. This provides a…
4. Unit 1: Data Models, Schemas, and Instances — 4.1 Data Models A Data Model is an abstract model that organizes elements of data and standardizes how they relate to one another and to properties of the real-world entities.…
5. Unit 1: Introduction to Distributed Data Processing — 5.1 What is Distributed Data Processing (DDP)? In a Distributed Database System , the data is stored on several computers. These computers communicate with each other through…
6. Unit 1: ER Model - Entities and Notation — 6.1 The Entity-Relationship (ER) Model The ER Model is the most widely used conceptual data model for database design. It allows designers to represent the "world" as a set of…
7. Unit 1: Detailed Analysis of Attributes — 7.1 What is an Attribute? Attributes are the specific properties or characteristics that describe an entity. For example, a STUDENT entity might have attributes like Name , Roll…
8. Unit 1: Keys in Depth — 8.1 The Importance of Keys In a database, we must be able to distinguish one entity from another. Keys are attributes that allow us to uniquely identify a record. 8.2 Types of…
9. Unit 1: Relationship Types and Constraints — 9.1 Relationship Concepts A Relationship is an association among several entities. For example, Student 'Amit' participates in a relationship with Course 'DBMS'. 9.2 Degree of a…
10. Unit 1: Weak Entities and Identifying Relationships — 10.1 What is a Weak Entity? An entity type that does not have a primary key of its own is called a Weak Entity Type . Owner Entity: The entity type on which the weak entity…
11. Unit 1: Enhanced ER - Specialization and Generalization — 11.1 Why Enhanced ER (EER)? Basic ER models are great for traditional applications, but they struggle with complex data (like CAD/CAM, GIS, or medical systems). The EER Model adds…
12. Unit 1: EER Constraints and Categorization — 12.1 Constraints on Specialization/Generalization There are two main types of constraints that define how entities can belong to subclasses. 1. Disjointness Constraint Disjoint…
13. Unit 2: Introduction to SQL and its Characteristics — 13.1 Overview of SQL SQL (Structured Query Language) is the standard language used to communicate with Relational Database Management Systems (RDBMS). It was originally developed…
14. Unit 2: SQL Data Types and Literals — 14.1 Understanding SQL Data Types Every column in a database table must be assigned a Data Type . This tells the DBMS what kind of data is allowed in that column and how much…
15. Unit 2: Types of SQL Commands (DDL, DML, DCL) — 15.1 Categorizing SQL Commands SQL commands are divided into several groups based on their functionality. 1. DDL (Data Definition Language) Used to define the structure of the…
16. Unit 2: Basic SQL Queries and Filtering — 16.1 The SELECT Statement The SELECT statement is used to fetch data from the database. 16.2 The WHERE Clause Used to filter records based on specific criteria. 16.3 The DISTINCT…
17. Unit 2: Logical Operators - AND, OR, NOT, BETWEEN, IN — 17.1 Combining Conditions 17.2 Range and List Filtering 17.3 Pattern Matching (LIKE)
18. Unit 2: Handling NULL Values — 18.1 What is a NULL Value? A field with a NULL value is a field with no value. It is very important to understand that a NULL value is different from a zero value or a field that…
19. Unit 2: Integrity Constraints - Primary Key, Unique, Check — 19.1 Implementation of Constraints Integrity constraints ensure that the data entering the database is accurate and reliable. Key Rules: PRIMARY KEY: Only one per table. UNIQUE:…
20. Unit 2: Referential Integrity (Foreign Keys) — 20.1 Referential Integrity Defined Referential Integrity ensures that the relationship between tables remains consistent. Specifically, it ensures that a value in the Foreign Key…
21. Unit 2: Aggregate Operators (Functions) — 21.1 Introduction to Aggregate Functions Aggregate functions perform a calculation on a set of values and return a single value. They are often used with the SELECT statement's…
22. Unit 2: The GROUP BY and HAVING Clauses — 22.1 The GROUP BY Clause The GROUP BY statement groups rows that have the same values into summary rows, like "find the number of students in each department". Syntax: 22.2 The…
23. Unit 2: Introduction to Nested and Correlated Queries — 23.1 What is a Subquery? A Subquery (or Nested Query) is a query within another SQL query. It is typically used to provide a value or a set of values to the outer query. 23.2…
24. Unit 2: SQL Joins - Inner and Left Outer Joins — 24.1 Why Joins? Data in a relational database is normalized and split into multiple tables. A JOIN clause is used to combine rows from two or more tables, based on a related…
25. Unit 2: Right Outer and Full Outer Joins — 25.1 Advanced Joins RIGHT JOIN Returns all records from the right table, and matched records from the left. FULL JOIN Returns all records when there is a match in either left or…
26. Unit 2: Views and Sequences — 26.1 SQL Views A View is a virtual table based on the result-set of an SQL statement. It contains rows and columns, just like a real table, but the data is not stored physically;…
27. Unit 2: Indexes and Performance — 27.1 Creating and Managing Indexes Indexes are used to speed up data retrieval. When to Index? Index columns used in WHERE clauses frequently. Index columns used in JOIN…
28. Unit 2: Triggers and Stored Procedures — 28.1 Implementation Examples Stored Procedure A reusable block of SQL code. Trigger Automatically executes on data changes. View A virtual table based on a query.

Unit 1: Comprehensive Overview of DBMS

1.1 What is a Database Management System?

A Database Management System (DBMS) is a complex software system that enables users to define, create, maintain, and control access to the database. It serves as an intermediary between the user and the database, ensuring that data is organized and easily accessible while maintaining security and integrity.

Fundamental Definitions

1.2 The Evolution: From File Systems to DBMS

Before the advent of DBMS, organizations relied on Traditional File-Based Systems. In this approach, each department (like Accounting or Sales) maintained its own set of files. This led to massive inefficiency.

Comparison Table: File System vs. DBMS

1.3 Real-World Applications of DBMS

Modern society runs on databases. Here are key sectors where DBMS is indispensable:

1. Banking: For tracking customer accounts, loans, and thousands of transactions per second. Accuracy and "Atomicity" are critical here.
2. Airlines: For reservations, flight schedules, and passenger manifests. Requires global, real-time concurrent access.
3. Universities: For student information, course registrations, and grade tracking.
4. E-commerce: For product catalogs, shopping carts, user profiles, and order history (e.g., Amazon, Flipkart).
5. Human Resources: For employee records, salaries, tax deductions, and performance reviews.

1.4 The Purpose of a Database System

The main goal of a database system is to provide a convenient and efficient environment for both retrieving and storing database information. It manages large bodies of information, involving both the definition of structures for storage and the provision of mechanisms for information manipulation.

Unit 1: Characteristics of the Database Approach

2.1 Self-Describing Nature of a Database System

Unlike traditional file systems, a database doesn't just contain the data itself; it also contains a complete definition or description of the database structure and constraints. This definition is stored in the DBMS Catalog (or Data Dictionary).

• Metadata: This "data about data" describes the structure of each file, the type and storage format of each data item, and various constraints on the data.
• Impact: This allows the DBMS software to work with different databases without being hard-coded for a specific structure.

2.2 Insulation Between Programs and Data (Program-Data Independence)

In traditional file processing, the structure of data files is embedded in the application programs. If you change the size of a field from 20 to 30 characters, every program accessing that file must be modified.

• DBMS Solution: The DBMS provides a conceptual representation of data. Application programs refer to this representation rather than the physical storage details.
• Data Abstraction: This allows the internal storage structure to change without affecting the application logic.

2.3 Support of Multiple Views of the Data

A database typically has many users, each of whom may require a different perspective or view of the database.

2.4 Sharing of Data and Multi-user Transaction Processing

a multi-user DBMS must allow multiple users to access the database at the same time. This is essential if data for multiple applications is to be integrated and maintained in a single database.

• Concurrency Control: The DBMS ensures that multiple users trying to update the same data do not interfere with each other (e.g., two travel agents booking the last seat on a flight).
• OLTP (Online Transaction Processing): A type of data processing that consists of executing a number of transactions occurring concurrently.

2.5 Summary of Database Approach Advantages

1. Controlling Redundancy: Storing data only once.
2. Restricting Unauthorized Access: Security and authorization subsystems.
3. Providing Persistent Storage: Objects survive after the program terminates.
4. Providing Storage Structures: Efficient search using Indexes and Hashing.
5. Providing Backup and Recovery: Protecting against hardware or software failure.

Frequently asked questions

Is the Database Management Systems course really free?

Yes. The entire Database Management Systems course on Siksha Sarovar is free to read with no account required. You can optionally sign in with Google to save your progress.

Do I get a certificate for Database Management Systems?

Yes — finish the lessons and pass the quiz to earn a free, verifiable certificate you can share on LinkedIn or with recruiters.

Can I run code while learning?

Yes. The built-in online compiler runs C, C++, Python, Java, PHP, JavaScript, C# and SQL directly in your browser — no installation needed.