（七）查询、修改、删除数据

--查询数据
select * from classes
select id,'bulise' name,createDate,address from classes where name='tony';--查询name='tony'的数据把name换成'tony'
select *,(select max(id) from classes)from classes where name='bulise';

--修改数据
update classes set name='hony',address='广东韶关' where id=7;

--删除数据（from可省略)
delete from classes where id=27