Database: Collection of related data organised for easy access, management & update.
DBMS: Software to create & maintain database (LibreOffice Base, MS Access, Oracle, MySQL).
Advantages: Centralised data, portability, multiple user access, reduced redundancy, timely info.
Components: Data, Hardware, Software, Users.
LIBREOFFICE BASE INTRODUCTION
Extension: .odb. Free & open source DBMS in LibreOffice suite.
KEY TERMS
Data: Raw facts ("Aneesh", 3031). Table: Rows & columns storing data. Field: Column (Student_Name). Record/Tuple: Row (one person's data). Entity: Real-world object (Student). Attribute: Property of entity (Name, DOB). Primary Key: Unique ID for each record (Admission No). Foreign Key: Field linking to primary key of another table. Relationship: Connection between tables. Query: Question to retrieve data. Form: Interface for data entry. Report: Formatted output for printing.
STEPS TO CREATE DATABASE
1. Create blank database (.odb). 2. Create tables (Design View/Wizard). 3. Define relationships (Tools → Relationships). 4. Create forms. 5. Create queries. 6. Create reports.
CREATING TABLES – DESIGN VIEW
Fields: Name, Type (Text, Number, Date), Description, Properties.
Primary Key: Right-click on field → Primary Key. Save: Ctrl+S → table name.
Data Types: Text [VARCHAR], Memo [LONGVARCHAR], Number [NUMERIC], Date [DATE], Time [TIME], Date/Time [TIMESTAMP], Currency [DECIMAL], Yes/No [BOOLEAN].
DEFINING RELATIONSHIPS
Path: Tools → Relationships → Add Tables → Drag primary key to foreign key.
Importance: Links tables to pull data together in queries.
CREATING FORMS
Methods: Wizard (step-by-step) or Design View (manual).
Form Wizard: Select fields → Add subform (optional) → Arrange layout → Set data mode → Apply style → Name & finish.
Modify Design: Right-click form → Edit → Change labels, fonts, align controls.
Controls: List Box (values from table), Push Button (actions), Check Box (Yes/No), Option Button (mutual choice).
CREATING QUERIES
Methods: Wizard or Design View.
Query Wizard: Select fields → Set sort → Set criteria → Choose detailed/summary → Name & finish.
Design View: Add tables → Select fields, alias, sort, visible, function, criterion.
Computational Field: Create calculated columns like "Salary*0.4" as DA.
CREATING REPORTS
Types: Static (fixed data) vs Dynamic (live data).
Report Wizard: Select fields → Set labels → Grouping → Sorting → Layout → Title → Choose static/dynamic → Finish.
ADVANCED EXAMPLE – LEDGER & VOUCHER FORMS
Tables: TBLADD_ACCOUNTS (ledger), tbTransactionMaster (vouchers).
Forms: frmCreateLedger (add accounts), frmTransactionMaster (voucher entry with combo boxes, buttons).
Queries: Payment Query, Receipt Query.
Reports: Payment Report, Receipt Report.
IMPORTANT EXAM QUESTIONS (CHAPTER 6 – 2018 to 2024)
Q1 (2020 Mar – 1 Mark): Tool to connect two tables in Base? Ans: Relationship.
Q2 (2020 Say – 1 Mark): Used to retrieve information from database? Ans: Query.
Q3 (2018 Mar – 2 Marks): Four DBMS software? Ans: MS Access, Oracle, MySQL, LibreOffice Base, PostgreSQL (any four).
Q4 (2018 Say – 2 Marks): Methods of creating forms? Ans: 1. Form Wizard (step-by-step). 2. Design View (manual drag & drop).
Q5 (2019 Mar – 2 Marks): Four DBMS components? Ans: Tables, Queries, Forms, Reports, Relationships (any four).
Q6 (2019 Say – 2 Marks): Explain Entity & Attribute with example. Ans: Entity: real-world object (Student). Attribute: property (Roll No, Name).
