Database Introduction – SS1 Digital Technologies Lesson Note (Third Term)

A database is an organised collection of related data stored so that it is easy to search, change and manage. A database management system (DBMS) is the software used to work with it. Data is kept in tables, where each column is a field and each row is a record. A primary key identifies each record.

Subject: Digital Technologies
Class: SS1

Behavioural objectives

By the end of the lesson, students should be able to:

1. Define a database and give examples.
2. State what a DBMS is and name common DBMS software.
3. List the things a DBMS does.
4. Explain what a table, a field and a record are.
5. Explain what a primary key is and give examples.

What is a database?

In your school, the principal needs to keep track of hundreds of students. They need to know your name, your class, your house address and your grades. If they kept all this on random scraps of paper, it would be a mess.

A database is an organised collection of related information (data) stored in a way that makes it easy to search, change and manage.

Real-life examples

• A phonebook: A database of names and phone numbers.
• Contacts app on your phone: A digital database of your friends.
• The school register: A database of student attendance.
• The library card catalogue: A database of books.

Why use a digital database?

A digital database is much faster than searching through a physical file. In a digital database, you can find one student out of 5,000 in less than a second.

What is a DBMS?

A database is just the “pile” of data. To work with it, you need a special tool called a DBMS (Database Management System).

Think of the database as the bank vault (where the money is kept) and the DBMS as the bank teller (the person who puts money in or takes it out for you). You do not just walk into the vault. You talk to the teller.

Common DBMS software

1. Microsoft Access: Great for beginners and small businesses.
2. MySQL: Used for big websites like Facebook and YouTube.
3. Oracle: Used by giant banks and governments.

What does the DBMS do?

• It lets you create a new place to store data.
• It lets you update data (like changing a student’s address).
• It lets you delete old data.
• It keeps the data secure so only the right people can see it.

What are tables?

In a database, information is stored in tables. A table looks like a grid in a spreadsheet (Excel), but it is much “stricter” about how data is entered.

A database can have many tables. For example, a “School Database” might have:

• A Students table.
• A Teachers table.
• A Subjects table.

By splitting information into different tables, the database stays neat and organised.

What are fields and records?

To understand how a table works, you need to know about fields and records.

Fields (the columns)

A field is a single category of information. In a student table, “First Name” is a field, and “Date of Birth” is another field.

• Vertical: Fields go up and down.
• Think of them as: The “questions” the database is asking.

Records (the rows)

A record is a complete set of information about one specific person or thing.

• Horizontal: Records go across the page.
• Think of them as: The “answers” for one person.

What is a primary key?

Every record in a table needs a way to be unique. Two students might have the same name (for example, two boys named “John Smith”). How does the computer tell them apart? We use a primary key.

A primary key is a field that is different for every record, like an Admission Number or a NIN. No two records can have the same primary key.

Key terms

Class activity

1. Design a table: If you were making a “Music Database”, what fields (columns) would you need? (For example, Song Title, Artist.)
2. Identify: Look at your school ID card. Which information on that card would be the primary key?
3. Discussion: Why is it better to store a phone number as a field than to write it in a long paragraph of text?

Evaluation

1. What is a database? Give two examples.
2. What is the job of a DBMS? Name two DBMS software packages.
3. State the difference between a field and a record.
4. Why do two students with the same name need a primary key?

Assignment

Design a “Students” table for your school. List at least five fields, say which field is the primary key, and write two sample records.