SQLBolt - Introduction
Link to lessons.
Introduction to SQL
What is SQL? Structured Query Language is a language used to create, maintain, and use relational databases. Thousands of applications from simple projects to Microsoft products use SQL through various formats and configurations.
Some use SQLite, MySQL, Postgres, Oracle, or Microsoft SQL, to name a few. Each use SQL as base, and include features that garner appeal from different developers.
Relational Databases
A relational database is a collection of 2D tables that are linked through some key value. All tables are made of a certain number of rows and columns.
| ID | Make/Model | # Wheels | # Doors | Type |
|---|---|---|---|---|
| 1 | Ford Focus | 4 | 4 | Sedan |
| 2 | Tesla Roadster | 4 | 2 | Sports |
| 3 | Kawasaki Ninja | 2 | 0 | Motorcycle |
| 4 | McLaren Formula 1 | 4 | 0 | Race |
| 5 | Tesla S | 4 | 4 | Sedan |
The lessons for this site are interactive, so I’ll do my best to link to the problems as I work on them.
Next: [[SQLBolt - Lesson 1|Lesson 1]]