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SQL Tutorial

SQL

Learning SQL

This tutorial on SQL gets you up to speed quickly.

Each page comes with real-world SQL examples.

Once you know SQL you can query and maintain databases.

This tutorial is designed for you, and it's free.

SQL Examples

#

All SQL examples in this tutorial solve a specific problem.
Here's an example.

SUPPLIER
Id
CompanyName
ContactName
City
Country
Phone
Fax
Problem: List all suppliers in reverse alphabetical order.
SELECT Id, CompanyName, ContactName, City, Country
  FROM Supplier
 ORDER BY CompanyName DESC

The answer to this problem is the given SQL query.
The table(s) on the right help with visualizing the query.

SQL Editor

Each SQL example has a  'Try It live'  button which opens the SQL Editor where you can change the SQL and run it against a live database.

SQL Editor

Tip:  The editor accepts SELECT, UPDATE, INSERT, DELETE, and other operations. Operations that change data or the data model will execute, but are then rolled back (undone) to maintain integrity of the database.


SQL for Beginners

If you're a beginner, then this tutorial is for you.

It covers the basics in a simple and easy-to-understand way.

The SQL editor lets you run your SQL -- a great learning experience.


SQL for Experienced Developers

As an experienced developer, this tutorial is also for you.

Our tutorial covers all SQL clauses, keywords, functions and more.

It is easy to forget an SQL detail or syntax -- this Guide has you covered.


You may also like

Each page ends with a 'You may also like' section with links to related topics, like so:



Last updated on Dec 21, 2023

Earn income with your data and sql skills
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