1. Meaning of Database
A database is an organised collection of related data. It allows information to be stored, searched, updated, and reported efficiently.
Examples include student admission records, library book lists, fee records, customer lists, and inventory records.
2. DBMS and Its Need
A Database Management System (DBMS) is software used to create and manage databases. It reduces repeated data, improves searching, and helps maintain accuracy.
- Stores related data in structured form.
- Allows fast searching and filtering.
- Supports forms for easier data entry.
- Creates reports for presentation.
- Helps protect important information.
3. Tables, Fields, and Records
A table stores data about one topic. A field is one category of information, and a record is one complete set of field values.
| Term | Meaning | Example |
|---|---|---|
| Table | Collection of related records | Students |
| Field | One column/category | Roll Number |
| Record | One complete row | One student's details |
4. Primary Key and Data Types
A primary key is a field that uniquely identifies each record. It should not be blank and should not repeat.
Common data types include text, number, date/time, yes/no, and decimal. Choosing the correct data type prevents incorrect entries.
5. Relationships
Relationships connect tables. For example, a Students table may connect with a Marks table using Roll Number.
Using related tables avoids storing the same data repeatedly. It also keeps updates more accurate.
6. Queries
A query asks the database to show selected information. Queries can filter, sort, calculate, or combine data from tables.
Example query: show students of Class 10 whose marks are greater than 80.
7. Forms
A form is a user-friendly screen for entering or viewing records. Forms reduce confusion because users can see one record or one set of fields at a time.
8. Reports
A report presents database information in a printable format. Reports are useful for class lists, result summaries, fee statements, and inventory summaries.
9. Good Database Practices
- Use clear table and field names.
- Choose a suitable primary key.
- Avoid duplicate records.
- Use correct data types.
- Back up important databases.
- Give access only to authorised users.
- Check reports before sharing them.
10. Revision Questions
1. What is a database?
A database is an organised collection of related data.
2. What is a primary key?
A primary key uniquely identifies each record in a table.
3. What is a query?
A query retrieves selected information from a database.
4. Why are forms useful?
Forms make data entry easier and reduce confusion.