Databases
Overview
Almost every organisation stores data: a shop's stock, a school's students, a library's books. A database is how that data is kept in a structured way so it can be searched, sorted and totalled in an instant. This topic shows you how a single-table database is built and how to pull exactly the data you want out of it using SQL.
You will learn how to define a single-table database from a set of requirements, choose suitable data types for each field, understand and pick a primary key, and read, complete and write SQL queries using SELECT, FROM, WHERE, ORDER BY, SUM and COUNT. By the end you should be able to design a table and query it confidently, just as the exam expects.
Objectives
- 1 Define a single-table database from given data storage requirements
- 2 Suggest suitable basic data types
- 3 Understand the purpose of a primary key and identify a suitable primary key for a given database table
- 4 Read, understand and complete structured query language (SQL) scripts to query data stored in a single database table
Lesson Note
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
Lesson Evaluation
Congratulations on completing the lesson on Databases. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- In a database, a single row containing all the fields about one object is called a: A. field B. record C. table D. query Answer: B
- Which data type is most suitable for a price such as 3.99? A. integer B. Boolean C. real D. character Answer: C
- What is the main purpose of a primary key? A. to sort the records B. to uniquely identify each record C. to count the records D. to encrypt the data Answer: B
- Which SQL clause is used to return only records that meet a condition? A. ORDER BY B. SELECT C. WHERE D. COUNT Answer: C
- Which SQL function counts how many records meet a condition? A. SUM B. COUNT C. ORDER BY D. TOTAL Answer: B
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
Recommended Books
Practice Mock Questions
Want to practice mock questions on Databases? Download the Green Bridge CBT app to access mock questions and full practice assessments for this topic.
Download The App On Google Playstore
Everything you need to excel in JAMB, WAEC & NECO
