SQL Tutorial_小百科

Learn SQL

SQL is a standard language for storing, manipulating and retrieving data in databases.

Our SQL tutorial will teach you how to use SQL in: MySQL, SQL Server, MS Access, Oracle, Sybase, Informix, Postgres, and other database systems.

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Examples in Each Chapter

With our online SQL editor, you can edit the SQL statements, and click on a button to view the result.

Example

SELECT * FROM Customers; Try it Yourself »

Click on the "Try it Yourself" button to see how it works.

SQL Exercises

Many chapters in this tutorial end with an exercise where you can check your level of knowledge.

See all SQL Exercises

SQL Examples

Learn by examples! This tutorial supplements all explanations with clarifying examples.

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SQL Quiz Test

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SQL References

At W3Schools you will find a complete reference for keywords and functions:

SQL Keyword Reference

SQL Data Types

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

SQL Data Types

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