SQL基本语句

小白从头复习数据库ing，整理了下最基本也是最常用滴SQL语句：

1.创建数据库：

CREATE DATABASE DBNAME

2.删除数据库

DROP DATABASE DBNAME

3.创建表

CREATE TABLE TABNAME(

    ID INT [NOT NULL][PRIMARY KEY],

    NAME VARCHAR(50)

)

4.修改表结构

添加一列：ALTER TABLE TABNAME ADD SEX CHAR

5.删除表

DROP TABLE TABNAME

6.插入

INSERT INTO STUDENT(XUEHAO,NAME) VALUES('8','4')

7.修改表中的值

UPDATE STUDENT SET CLASS='19' WHERE XUEHAO='3'

8.删除

DELETE FROM STUDENT WHERE NAME='123'

9.查询

SELECT * FROM STUDENT WHERE NAME='PIG'

SELECT NAME FROM STUDENT WHERE NAME LIKE '王%'

SELECT NAME FROM STUDENT ORDER BY XUEHAO [DESC]

SELECT COUNT(CLASS) FROM STUDENT

SELECT COUNT(DISTINCT CLASS) FROM STUDENT 不重复的

SELECT AVG(AGE),SUM(AGE),MAX(AGE),MIN(AGE) FROM STUDENT

SELECT TOP 10 NAME FROM STUDNET

========

待续