说明：  SQL(Structured Query Language，结构查询语言)是一个功能强大的数据库语言。SQL通常使用于数据库的通讯。ANSI（美国国家标准学会）声称，SQL是关系数据库管理系统的标准语言。SQL语句通常用于完成一些数据库的操作任务，比如在数据库中更新数据，或者从数据库中检索数据。虽然绝大多数的数据库系统使用SQL，但是它们同样有它们自立另外的专有扩展功能用于它们的系统。但是，标准的SQL命令，比如"Select"、 "Insert"、 "Update"、 "Delete"、 "Create"和 "Drop"常常被用于完成绝大多数数据库的操作。
(SQL (Structured Query Language, Structure Query Language) is a powerful database language. Often used in a SQL database communications. ANSI (American National Standards Institute) said, SQL is a database management system standard language. SQL statements are usually used to complete some tasks of database operations, such as updating the database data or from the database retrieval of data. Although the majority of the SQL database system, But they also have their self-reliance another extension of the exclusive function for the system. However, the standard SQL commands, such as "Select", "Insert", "Update", "Delete" "Back" and "Drop" is often used to complete the majority of database operation.)