CRUD操作
create 创建
read 读取
update 修改
delete 删除


select code ,name from info 读取特定值
select * from info where code=‘p003‘ 条件查询
select * from info where code=‘003‘ or nation=‘n002‘ 或的关系 必须有一个满足条件
select * from info where sex=0 and nation=‘002‘ 与的关系 两种都包括
select * from info where like ‘_奥迪%‘
select * from info order by code 升序asc 降序 desc

insert into info values(‘‘,值) 自增长列的处理

delete from info where code=‘p002‘删除数据

update info set name=‘梁振‘，sex=1 where code=‘p003‘