In this presentation, we dive into the overall structure of a Database Management System. Understand how a DBMS is organized internally and explore its core components such as the query processor, storage manager, buffer manager, and transaction manager. This lecture breaks down the architecture to help you see how different layers interact to handle user queries and data storage efficiently. A must-watch for CS/IT students and aspiring database professionals!

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Overall System Structure
Session No.: 2
Course Name: Database Management Systems
Course Code: E1UA211B
Instructor Name: Aishwarya
Duration: 50 min

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• Introduction to Database
• Need of Database Management System
• File System vs DBMS
Review of Session No.1

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Reflect on the
responses of post
session activity of
previous session /
pre-session
activity of this
session
Reflect on the
responses of post
Session Activity

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Reflect on the
responses of post
session activity of
previous session /
pre-session
activity of this
session
Opening
What security measures do you think a DBMS should
implement to protect data?

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LEARNING
OUTCOMES
LO1
• Describe the Core Components of a DBMS
At the end of this session students will be able to

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Session
Outline
1. Basic terminologies in DBMS
2. Learning Concept of Activity 1
3. A1(Jigsaw Activity)
4. Conclusion & Closing Activity

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Concept and
Definition for
Learning Activity 1

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Data Models, schemes and Instance
Data abstraction generally refers to the suppression of details of data organization
and storage, and the highlighting of the essential features for an improved
understanding of data.
Data Models- collection of concepts that can be used to describe the structure of a
database- provides the necessary means to achieve this abstraction.
A Schema defines the overall structure of a database, including tables, attributes,
constraints, and relationships. It acts as a blueprint for database design.
A Database Instance is the actual data stored in the database at a particular
moment. It is a snapshot of the database content at a specific point in time.

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Schema vs. Instance
Schema = Structure of the database (remains constant).
Instance = Data inside the database at a given time (changes frequently).

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Components of a Database System

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Components of a Database System
1. Query Processor
 Translates user queries into executable instructions.
 Components:
• DML Compiler – Converts DML statements into low-level instructions.
• DDL Interpreter – Processes DDL statements to manage metadata.
• Embedded DML Pre-compiler – Converts embedded DML in applications to
procedural calls.
• Query Optimizer – Enhances query execution efficiency
2. Storage Manager
 Acts as a bridge between the database and queries.
 Maintains data consistency, integrity, and security.
 Components:
• Authorization Manager – Controls user access.
• Integrity Manager – Enforces database constraints.
• Transaction Manager – Manages concurrent transactions.
• File Manager – Organizes database files.
• Buffer Manager – Handles memory optimization.

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Components of a Database System
 Disk Storage
• Data Files – Store actual data.
• Data Dictionary – Maintains metadata.
• Indices – Enable faster data retrieval.

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Learning Activity 1(30 min)
Step 1: Formation of Expert Groups (5
min)
Divide the class into 4-5 groups, each assigned a specific DBMS system
component
• Query Processor (Parsing, Optimization, Execution)
• Storage Manager (Buffer Manager, Disk Storage, File Organization)
• Transaction Manager (ACID properties, Concurrency Control)
• Access Control & Security (User Authentication, Authorization)
Provide each group with reading materials and guiding questions on their
assigned component.
Step 1: Formation of Expert Groups (10 min)
• Each group discusses and becomes "experts" on their assigned
DBMS component.
• Encourage them to take notes, summarize key points, and prepare
examples.
• The teacher moves around, guiding discussions and clarifying
doubts.

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Learning Activity 1(30 min)
Step 3: Jigsaw Groups (10 min)
• Reorganize students into new groups, ensuring each group has one expert
from each DBMS component.
• Each expert teaches their section to their peers in the new group.
• Other members ask questions to deepen understanding
Step 4: Class-Wide Sharing & Discussion (5 min)
• Select students to present a summary of each DBMS component.
• The teacher reinforces key points and addresses misconceptions.

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Summary
A. Users: End-users, application programmers, database administrators (DBAs).
B. Query Processor: Handles query parsing, optimization, and execution.
C. Storage Manager: Manages data storage, indexing, and transactions.
D. Buffer Manager: Controls data transfer between disk and memory.
E. Transaction Management: Ensures ACID properties (Atomicity, Consistency,
Isolation, Durability).
F. Disk Storage & File System: Stores database files on physical storage.

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Ensure attainment of LOs in alignment to the
learning activities: outcomes (1-2)
LO1: Describe the Core Components of
a DBMS
LO2: Explain the Three-Level
Architecture of DBMS

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Discussion on the post session
activities
Attempt the Post-session activity on LMS, before next session

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Information to next topic of the
course
Next session:
Three-Level Architecture

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Review and Reflection
from students

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