SQL简介

1. What is SQL?

   • SQL是一个通用的操纵数据库的语言

2. SQL Statemente Classes

   SQL schema statements

   be used to define the data structures stored in the db.

   SQL data statements

   be used to manipulate the data structures which previously defined using SQL schema statements;

   SQL transaction statments

   be used to begin, end and roll back transactions.

   nonprocedural language