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SQL 教程

SQL主页 SQL简介 SQL语法 SQL选择 SQL选择 Distinct SQL位置 SQL运算符 SQL排序依据 SQL插入 SQL空值 SQL更新 SQL删除 SQL选择 Top SQL最小和最大 SQL计数 SQL喜爱 SQL通配符 SQL输入 SQL之间 SQL别名 SQL连接 SQL输入ner Join SQL左联接 SQL右连接 SQL完全联接 SQL自连接 SQL联盟 SQL分组依据 SQL具有 SQL存在 SQL全部 SQL选择 Into SQL插入 Select SQL案例 SQL空函数 SQL存储过程 SQL注释 SQL运算符

SQL 数据库

SQL创建数据库 SQL Drop DB SQL备份数据库 SQL创建表 SQL删除表 SQL变更表 SQL约束 SQL不为空 SQL唯一 SQL主键 SQL外键 SQL检查 SQL默认值 SQL输入dex SQL自动增量 SQL日期 SQL视图 SQL输入jection SQL托管 SQL数据类型

SQL 参考

SQL关键字 MySQL函数 SQL Server函数 MS Access功能 SQL快速参考

SQL 示例

SQL 示例 SQL测验 SQL 练习 SQL证书

SQL Tutorial

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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示例 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;
来试试吧 »

Click on the "来试试吧" button to see how it works.


SQL 练习

Test Yourself With 练习

Exercise:

Insert the missing statement to get all the columns from the Customers table.

 * FROM Customers;

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SQL 示例

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

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SQL测验 Test

Test your SQL skills at W3Schools!

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SQL 参考

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

SQL Keyword 参考

MYSQL Functions

SQLServer Functions

MS Access功能

SQL快速参考erence


SQL数据类型

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

SQL数据类型


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