Left Arrow



The icon of the Adeptus Mechanicus. A cog with a skull at the center.

3 rectangles stacked on top of 1 another.



Status: decay

SQL (Structured Query Language) enables users to interact with relational databases. Data is structured in tables. Each table has:

  • 1 column for each field and
  • 1 row for each record.
A table of data

An SQL statement is composed of:

  • an ordered list of clauses (example: SELECT, FROM, WHERE, …),
  • each clause has its own syntax and
  • each statement ends in ';'.



SELECT class
FROM fleet;

The above query will return the class column values for all rows in the fleet table.

An elephant's head.


A Relational Database Management System enables a user to define, create, maintain and control access to the database. The system that will accept your SQL query to and return a result. Some of the most common RDBMSs are:

  • Microsoft Azure SQL Database
  • MySQL
  • PostgreSQL (or Postgres)
  • SQLite

Due to its popularity, all examples in this digital garden will be referring to Postgres.

Where to Next?

Arrow pointing downYOU ARE HERE
A sci-fi robot taxi driver with no lower body