mysql常用语句:

登陆mysql:

mysql -u root -p password

创建数据库:

create database dbname;

删除数据库:

drop database dbname;

说明:备份sql server
--- 创建 备份数据的 device
USE master
EXEC sp_addumpdevice 'disk', 'testBack', 'c:\mssql7backup\MyNwind_1.dat'
--- 开始 备份
BACKUP DATABASE pubs TO testBack
 

查看数据库:

show databases;

查看某一数据库的表:

use newcms;

show tables;

创建新表:(根据旧表建立新表)create table tab_new as select col1,col2… from tab_old definition only

删除新表
drop table tabname
 

6、说明:增加一个列
Alter table tabname add column col type

:列增加后将不能删除。DB2中列加上后数据类型也不能改变,唯一能改变的是增加varchar类型的长度。
7、说明:添加主键: Alter table tabname add primary key(col) 
说明:删除主键: Alter table tabname drop primary key(col) 
8、说明:创建索引create [unique] index idxname on tabname(col….) 
删除索引:drop index idxname
注:索引是不可更改的,想更改必须删除重新建。
9、说明:创建视图create view viewname as select statement 
删除视图drop view viewname

查看其中一个表的全部内容:

select * from cms_usercms;

这是一个保存用户名密码的表,对这个表做操作:

查询:

查找select * from table1 where field1 like ’%value1%’ 
排序select * from table1 order by field1,field2 [desc]
总数select count as totalcount from table1
求和select sum(field1) as sumvalue from table1
平均select avg(field1) as avgvalue from table1
最大select max(field1) as maxvalue from table1
最小select min(field1) as minvalue from table1

插入:insert into table1(field1,field2) values(value1,value2)

删除:

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转载自www.cnblogs.com/fangwenchen/p/9326607.html