1. ANSI SQL1992 − Database Language SQL (Proposed revised text of DIS 9075) July 1992 (Second Informal Review Draft).
2. SQL 1999 - 知名的1999更新
3. Structured Query Language (SQL) − DB2 resource for SQL users.
4. Oracle SQL Developer − Oracle自己的数据库管理客户端/Oracle SQL Developer is a free and fully supported graphical tool for database development.
5. SQL at Wikipedia − A small article on SQL, worth to go through it.
6. MySQL官方网站 Official Website − Here you can download the latest MySQL release, get the MySQL news update. The mailing list is also a great resources for anyone who want to build dynamic websites using MySQL.
7. MSSQL (SQL Server)官网网站 - 微软的数据库，我用得最多的。