How to Get Started with SQL Querying

No Medium subscription? Read here — Free Access

Are you embarking on a journey to become a data analyst, data scientist, or software developer, there is one essential skill in all of these positions: SQL Structured Query Language, SQL is the backbone of data management and manipulation, from extracting valuable insights to building powerful software applications and databases. In this beginner tutorial, we will guide you through your first steps in querying a relational database.

For this tutorial, we will use a simple MySQL database with 3 tables: student, mark, and course. The student table contains 3 columns student_number, first_name, and last_name. The course table has 2 columns course_code and course_name. The mark table contains 3 columns course_code, student_number which are foreign keys, and the mark column.

Note that MySQL is just one of many relational databases.

Database ER diagram

The database and the code used in this tutorial can be found at this repository: https://github.com/CaloloCosta/How-to-Get-Started-with-SQL-Querying

So without further ado let’s get started…

1. SELECT Statement