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SQL语句大全

--说明:创建数据库

create database USER(表名)

--说明:删除数据库

drop database USER(表名)

--说明:备份 sql server

--创建备份数据的  device

USE master

EXEX sp_addumpdevice 'disk','testBack','C:\mssql17backup\MyNwi'

nd_1.dat'

--开始备份

BACKUP DATABASE pibs TO testBack

--说明:创建新表

create table tabname(col1 type1 [not null] [primary key],col2 type2 [not null]),

--根据已有的表创建新表:

A:create table tab_new like tab_old (使用旧表创建新表);

B:create table tab_new as select col1,col2… from tab_old definition only

--说明:删除新表

drop table tabname

--说明:增加一个列

Alter table tabname add column col type

--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)

--说明:创建索引

create [unique] index idxname on tabname(col….)

--删除索引

drop index idxname 

--说明:创建视图

create view viewname as select statement

--说明:删除视图

drop view viewname

--说明:几个最简单的基本的sql语句

条件:select * from table1 where (条件)

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

删除:delete from table1 where(条件)

跟新:update table1 set field1=value1 where (条件)

查找:select * from table1 where field1 like ’%value1%’ ---like

排序:select * from table1 order by field1,field2 [desc]或者[asc]

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

外连接:left (outer) join

本文转自12691034博客51CTO博客,原文链接http://blog.51cto.com/12701034/1929636如需转载请自行联系原作者

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