1. Which of the following is a correct SQL statement to select all records from a table named ‘Customers’?
EXTRACT * FROM Customers;
SELECT ALL RECORDS Customers;
✔ SELECT * FROM Customers;
2. Which comparison operator checks if text matches a pattern?
IN
✔ LIKE
BETWEEN
3. Which comparison operator is used to check for one value being greater than the other value?
<>
✔ >
==
4. Which SQL keyword is used to create an alias for a column or table?
✔ AS
ALIAS
ALIAS COLUMN
Basic Syntax:
SELECT column_name FROM table_name;
Example: Selecting student names and IDs from a students table:
SELECT student_id, name FROM students;
To select all columns, use *:
SELECT * FROM students;
Syntax:
SELECT column_name AS alias_name FROM table_name;
Example: Renaming columns in the result set:
SELECT product_name AS Product, price AS “Price (USD)” FROM products;
Table Aliases:
SELECT s.name FROM students AS s;
| Operator | Description | Example |
| = | Equal to | WHERE age = 30 |
| != or <> | Not equal to | WHERE city != ‘London’ |
| > | Greater than | WHERE salary > 50000 |
| < | Less than | WHERE age < 40 |
| >= | Greater than or equal to | WHERE score >= 90 |
| <= | Less than or equal to | WHERE height <= 5.5 |
| BETWEEN | Within a range (inclusive) | WHERE age BETWEEN 20 AND 30 |
| IN | Matches multiple values | WHERE department IN (‘HR’, ‘Finance’) |
| LIKE | Pattern matching | WHERE name LIKE ‘J%’ |
Filter by a specific condition:
SELECT * FROM employees WHERE age = 30;
Exclude certain values:
SELECT * FROM employees WHERE age != 30;
Filter using ranges (BETWEEN):
SELECT * FROM employees WHERE age BETWEEN 30 AND 40;
Check if a value exists in a set (IN):
SELECT * FROM employees WHERE name IN (‘Alice’, ‘Bob’);
Find names that start with “J”:
SELECT * FROM students WHERE name LIKE ‘J%’;
Find names that end with “s”:
SELECT * FROM students WHERE name LIKE ‘%s’;
Find names that contain “ar” anywhere in them:
SELECT * FROM students WHERE name LIKE ‘%ar%’;
✔ SELECT retrieves data from a database.
✔ Aliases (AS) make query results more readable.
✔ Comparison operators allow filtering specific data.
✔ LIKE is used for pattern-based searches.
✔ BETWEEN, IN, and other conditions help refine queries.
1. What is a database schema?
Defines a type of software used for database management. Data is structured and stored by relationships, through tables.
✔ Defines how data is structured, stored and related. It describes the tables, fields, data types and relationships in the database.
Defines how unstructured data is stored without the use of the tables or fields. There are the same data types in the database
.
2. Which SQL statement is used to create a new table called “Products” with a column “ProductID” of type integer?
✔ CREATE TABLE Products (ProductID int);
USE TABLE Products (ProductID int);
CREATE TABLE Products (ProductID integar);
3. True or False: A Primary Key is a unique identifier
✔ True
False
4. What is the correct SQL command to insert the values into the “Orders” table?
INSERT Orders NEW (value1, value2);
✔ INSERT INTO Orders VALUES (value1, value2);
ADD INTO Orders VALUES (value1, value2);
Example:
CREATE DATABASE intro_to_data;
USE intro_to_data;
Example:
CREATE TABLE equipment_maintenance (
equipment_id INT,
maintenance_cost DECIMAL(10,2),
description VARCHAR(255),
is_operational BOOLEAN,
last_maintenance_date DATE
);
Example:
INSERT INTO equipment_maintenance VALUES
(101, 2500.75, ‘Engine maintenance’, TRUE, ‘2024-01-01’),
(102, 500.00, ‘Aircon maintenance’, FALSE, ‘2023-12-15’);
| Constraint | Function |
| NULL | Allows empty values |
| NOT NULL | Prevents empty values |
| UNIQUE | Ensures unique values in a column |
| PRIMARY KEY | Uniquely identifies a row (combination of NOT NULL & UNIQUE) |
| FOREIGN KEY | Links a column to another table’s primary key |
Example: Adding constraints while creating a table
sql
CREATE TABLE equipment (
equipment_id INT PRIMARY KEY,
name VARCHAR(255) NOT NULL,
type VARCHAR(255) NOT NULL
);
Example:
sql
CREATE TABLE customers (
customer_id INT PRIMARY KEY,
first_name VARCHAR(50),
last_name VARCHAR(50),
email VARCHAR(100)
);
Example:
sql
CREATE TABLE maintenance_log (
log_id INT PRIMARY KEY,
equipment_id INT NOT NULL,
maintenance_date DATE,
FOREIGN KEY (equipment_id) REFERENCES equipment (equipment_id)
);
| Error | Possible Fix |
| Missing semicolon (;) | Ensure statements end with ; |
| Reserved word error | Check SQL syntax and keywords |
| Connection issues in DBeaver | Ensure MySQL is installed & configured correctly |
| Error inserting data | Check constraints (e.g., NOT NULL, UNIQUE) |
1.5 Cyber Warfare
Cyberwarfare involves using technology to attack a nation’s computer systems, causing disruption or physical damage. One major example is the Stuxnet malware, a sophisticated cyberweapon used to target Iran’s nuclear enrichment program.
Cyberwarfare is used to gain a strategic advantage over adversaries by disrupting critical infrastructure or stealing sensitive information.
Cyberwarfare represents a growing threat in modern conflicts, where attackers can cause significant disruption without physically entering a targeted country.
1.4 Cyber Attackers
Attackers exploit vulnerabilities for personal or financial gain. They are categorized into white hat, gray hat, and black hat attackers.
Cyber attacks originate from both inside and outside an organization.
1.2 Organisational Data
Traditional data is generated and maintained by organizations and includes:
IoT refers to a network of connected devices that collect and share data. With the growth of IoT, Big Data has become a significant technological and business focus.
The McCumber Cube is a cybersecurity model that evaluates security initiatives using three dimensions:
Phishing is a common cyber threat. Example:
1.1 The World of Cybersecurity
Cybersecurity is the practice of protecting individuals, organizations, and governments from digital attacks by safeguarding networked systems and data from unauthorized use or harm.
Personal data includes any information that can identify you and exists both online and offline.
Choosing a secure username is crucial. Recommended examples: ✔ jdoe
✔ j.doe12
Avoid including full names, job roles, or birth years to protect privacy.
Personal data includes names, social security numbers, birth details, and private messages. Cybercriminals use this information for fraud and impersonation.
Once shared, data can be copied, stored, and distributed without control.
Every time personal data is collected or shared, security risks arise.
Computing devices not only store personal data but also generate new data about users.
Cybercriminals target personal data for financial gain.
Cybercriminals use stolen data for long-term financial and personal exploitation.
It’s not just criminals who seek personal data:
+
+
+
+
+
+
Currency Exchange Project (Intro blog coming soon!) is a small project created by a group of junior programmers aiming to build a Python application that integrates APIs, frameworks, and potentially other technologies. The goal here is to gain a better understanding of workflows commonly used in the ‘developer world’.
This project serves as a great learning opportunity for our future, including GitHub repositories and blog posts.
Before diving into our code, let’s first explain some key terminology. ʕっ•ᴥ•ʔっ
What is an API?
An API (Application Programming Interface) is a way for different software or services to communicate. It works like a waiter in a restaurant, taking requests, delivering them to the system, and returning a response.
For example, when using Google Maps, the app sends a request to Google’s API, which retrieves the necessary data and sends it back for display.
APIs exist in many forms, some follow established standards like HTTP, while others extend or build upon these, such as REST. Creating an API can involve anything from defining custom protocols and data structures to developing simple interfaces for utility libraries. In web applications, APIs commonly serve as the connection points between various underlying services.
In basic terms is API broadly refers to the code used to interact with a library or service. Typically, users only need to know how to use it, not how it operates internally
How do we import it?
First, let’s check what version of python we have, we do this by (in bash)
‘py –version’
We can see the output being ‘python 3.13.1’, basically meaning python3. Now knowing that we can do the next step
Since we are using python we have to ensure that we have installed some API tools within our systems. The command we do this is the following (this would depend on your device):
‘Py -m pip install requests’
You know it would work through a lot of output of ‘downloading’ stuff. If it doesn’t, you already have it, or your command is a little different due to a different system/ terminal. Google is your best friend there.
Now we need to create a virtual environment for our project. We do this by typing:
‘py -m venv venv’
The reason we do this is to ensure that each project has its own virtual environment, keeping it separate from other projects. Without a virtual environment, all dependencies would be installed globally, which can lead to conflicts if different projects require different versions of the same package. This can cause interference and potentially break everything.
With Linux users, installing packages globally can be risky because the operating system relies on Python internally. Modifying system-wide Python packages could disrupt essential system functions.
As a best practice, always create a virtual environment for every project, whether it’s a personal or group project. This keeps dependencies organised, prevents conflicts, and ensures a stable development environment.
Next let’s import the library at the top of the page. We do this by typing:
‘Import requests’
For our project, we would be importing JSON, making it easy to parse and extract the required currency rates. We do this by:
‘Import json’
Importing API
Now, we need to store the API in a variable so that we can call it easily instead of pasting that long link everywhere it’s needed. Since the project heavily relies on this API, it would be used everywhere!
Printing API
Now, let’s print the contents. First, I will fetch the data from the API, then convert it into JSON format, and finally print it to the console. Easy, innit!
This is what i have come up with:
‘all_currencies_response = requests.get(currency_value_API)’
‘currency_data = all_currencies_response.json()’
‘print(json.dumps(currency_data, indent=4))’
This is the result:
We can see that using the json has formatted the code quite nicely and in a readable manner. And it wasn’t so hard to do it.
Next we might learn how to print/ search for specific currencies and have a better understanding of the first pull request of the project . Now let’s code ‘em all! ʕ -ᴥ•ʔ♡
Credits
Resources
1. Which description best defines data?
Data is strictly numerical information used in science.
✔ A collection of recorded information that can be analysed to make decisions.
Information that is only useful for technology experts
2. What is the difference between structured and unstructured data?
Unstructured data is organised and searchable, whereas structured data isn’t searchable.
✔ Structured data is highly organised and easily searchable, whereas unstructured data is not easily searchable and lacks a predefined format.
Structured data cannot be stored in databases, but unstructured data can.
3. What is SQL?
A tool for extracting and analysing data
✔ SQL is a programming language used specifically for communicating with RDBMs.
A database management system
4. Which of the following is an example of structured data?
A video file uploaded to a streaming platform
✔ A database table with customer names, addresses, and phone numbers
A collection of PDF documents
KaiRaiChu 