经常使用的sql语句总结之数据处理（DML）

数据处理 DML

1)增

1.1 增添一条记录

insert into [表名](,,,,,) values(,,,,,) 

1.2 从其它表中拷贝数据

insert into [表名]
select .... from [另外一个表] 

where ....

2)改
update [表名]

set ..... 

where ....

3)删
delete from [表名] where ....

4)查(最经常使用的数据库操做)

select ....from ...where ....group by ...having ... order by .... 

查找：select * from table1 where field1 like ’%value1%’ ---like的语法很精妙，查资料! 

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