mysql语句大全
mysql 与 mssql 语法十分相似，懂一门另一门也就差不多了，下面来总结 mysql 都有哪些语句。
1、登录 mysql
语法如下：mysql -u用户名 -p用户密码
例：
1）登录本机：mysql -uroot -p123456
2）远程登录：mysql -h192.186.210.69 -uroot -p123456 /*-h后是IP地址*/
2、启动和停止 mysql 服务
启动：net start mysql
停止：net stop mysql
3、创建与删除数据库
创建：CREATE DATABASE 数据库名
删除：drop database 数据库名
4、打开（使用）数据库
use 数据库名
5、创建表
create table tablename(column1 type1 [not null] [primary key],column2 type2 [not null],…)
例：create table employee(id int not null primary, ename varchar(30))
根据已有表创建新表：
1）create table newtable like oldtable (使用旧表创建新表)
2）create table newtable as select column1,column2,… from oldtable definition only
6、删除表
drop table tablename
7、查询
select column1,column2,… from tablename where 条件 order by field1,[field2,…] [ASC | DESC]
例：
select ename,age from employee where age > 25 order by age; -- 按年龄升序排列
select distinct ename,age from employee order by age desc; -- 按年龄降序排列
select ename,age from employee where ename like '%李%'; -- 查找包含“李”的记录
select max(age) from employee; -- 最大值
select min(age) from employee; -- 最小值
select count as totalRecord from employee; -- 统计总数
select sum(age) from employee where age > 25; -- 求和
select avg(age) from employee where age > 25; -- 求平均值
select ename from employee where ename in(select ename from users); -- 子查询
8、插入
insert into tablename(field1,field2,…)values(value1,value2,…)
例：insert into employee(id,ename,age) values(1,'李大海',26);
9、更新
update tablename set field1=value1,field2=value2,… where 条件
例：update employee set age=28 where ename='李大海';
10、删除
delete from tablename where 条件
例：delete from employee where id > 100
11、增加删除列
增加列：Alter table tablename add column columnname type [[after|before] column]
例：Alter table employee add column address varchar(50) before age;
Alter table employee add column address varchar(50) after age;
删除列：Alter table tablename drop column columnname
例：Alter table employee drop column address;
重命名列：Alter table tablename change oldcolumnname newcolumnname type
例：Alter table employee change address useraddr varchar(50);
修改列类型：Alter table tablename modify columnname type
或：Alter table tablename change columnname columnname type
例：Alter table employee modify address char(100);
Alter table employee change address address char(100);
12、重命名表
rename table oldtablename to newtablename
例：rename employee to user;
13、创建删除索引
创建：create [UNIQUE|FULLTEXT|SPATIAL] index indexname on tablename(column1,column2,…)
例：create unique index emp_ename on employee(ename);
删除：drop index indexname
例：drop index emp_ename;
14、添加删除主键
添加：Alter table tablename add primary key(column1,column2,…)
例：Alter table employee add primary key(ename,id);
删除：Alter table tablename drop primary key(column1,column2,…)
例：Alter table employee drop primary key(ename,id)
15、创建删除视图
创建：create view viewname as select statement
例：create view v-employee as select ename,age from employee;
删除：drop view viewname
例：drop view v-employee;