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Start learning SQL


May 16, 2021 03:00 SQL


Table of contents


Start learning SQL

SQL is the standard computer language for accessing and processing databases.

In this tutorial, you'll learn how to use SQL to access and process data from data systems such as MySQL, SQL Server, Access, Oracle, Sybase, DB2, and other database systems.


Examples of each chapter


Each chapter provides a simple example of SQL.

SELECT * FROM Customers;

Start learning SQL!

SQL queries select all records from the user table:

SELECT * FROM users;

SQL queries remove a single record from a user table by using the where clause:

DELETE FROM users WHERE user_id=299;

Suitable for people


The purpose of this reference is to help beginners learn SQL languages in depth.


SQL quiz test


Test your SQL skills at w3cschool!

Start the SQL quiz!


SQL Quick Reference


An SQL quick reference. Print and put it in your pocket.

SQL Quick Reference


SQL data type


Data types and scopes for Microsoft Access, MySQL, and SQL Server.

SQL data type


W3Cschool combat certification


It is well known that obtaining a certificate is the best proof of a programming example

Go through the customs



Learning prerequisites


This reference prepares a variety of examples, and before you officially begin the exercise, I assume that you already know what a database is, especially a relationship database management system (RDBMS), and what a computer programming language is.