Database Management System (LibreOffice Base)
Complete CBSE Class 10 IT (Code 402) textbook coverage for RDBMS concepts: Relational Data Models, Primary & Foreign Keys, Table Design in Base, Referential Integrity, SQL Query Syntax, Interactive Forms, and Formatted Reports.
Browse Dedicated Chapter Notes & Solved MCQs
Database Concepts
RDBMS vs Flat File, Primary & Foreign Keys.
Create & Edit Tables
Design View, Data Types & Primary Key setup.
Table Operations
Sorting, Filtering & Referential Integrity.
Retrieve Data (SQL)
Design View & SQL Statements (SELECT, WHERE).
Forms & Reports
Form Wizard, Sub-Forms & Report formatting.
Key Concepts At A Glance (Unit 3 Cheat Sheet)
Essential database theory, terminology, data types, relational integrity rules, and SQL query syntax:
Primary: Unique, never NULL.
Candidate: Eligible to be primary.
Alternate: Remaining candidate keys.
Foreign: Links to parent primary key.
CHAR: Fixed length padding.
VARCHAR: Dynamic variable length.
INTEGER / DECIMAL: Numerical values.
DATE / TIME: Temporal types.
Tools > Relationships: 1:1, 1:Many, Many:Many. Rules: No Action (blocks delete), Delete Cascade (purges child rows), Set NULL.
SELECT f1, f2 FROM Tab WHERE cond ORDER BY f1 DESC;
Wildcards: % (any length), _ (single char).
Appreciate the Characteristics of a Database
A Database is an organized collection of related data. While traditional flat-file systems suffer from duplication, inconsistency, and poor access controls, a Relational Database Management System (RDBMS) organizes information into structured tables connected by relational keys.
Core Relational Terminology
A single horizontal row representing all details of one specific entity (e.g. Roll No 101, Name 'Rohan', Grade 10).
A vertical column storing a single category of data for all records (e.g., StudentName, BirthDate, Marks).
Degree: Total count of columns/fields.
Cardinality: Total count of rows/records.
Types of Relational Keys (Guaranteed Board Exam Question)
Relational keys guarantee that records are retrieved without ambiguity and prevent duplicate or corrupted data:
A column that uniquely identifies each record in a table. It cannot accept duplicate values and can NEVER be NULL (e.g. Admission_Number, Aadhaar_Number).
Candidate Keys: All fields capable of serving as a primary key (e.g. RollNo, Email, PassportNo).
Alternate Key: The candidate keys that were NOT picked as the primary key.
When no single field is unique, a combination of two or more attributes forms the primary key (e.g. FlightID + FlightDate).
A field in a child table that references the primary key of another parent table to establish a relational link. Unlike primary keys, foreign keys can contain duplicate values and can be NULL.
Unit 3 Solved MCQs (10 High-Yield Questions)
Directly curated from curriculum chapter-end self-assessment exercises and CBSE sample papers.
In Relational Database Management Systems (RDBMS), what do 'Degree' and 'Cardinality' refer to?
Which of the following database key types can NEVER contain NULL values and must uniquely identify each record in a table?
What is the key difference between CHAR and VARCHAR data types in LibreOffice Base?
When a table has two or more columns combined together to serve as the Primary Key, it is known as a:
In LibreOffice Base, what is the default file extension for a registered database document?
What is Referential Integrity in relational databases?
Which Referential Integrity option deletes all related child records automatically when a parent record in the primary table is deleted?
In SQL queries, which wildcard character in LibreOffice Base represents zero, one, or multiple characters when using the LIKE operator?
Which database object in LibreOffice Base provides an interactive user-friendly graphical interface specifically designed for data entry and record viewing one at a time?
What is the primary purpose of a 'Report' in LibreOffice Base?
Frequently Asked Board Questions (Base Unit 3)
Detailed model answers strictly formulated according to official CBSE marking criteria: