update 表名 set 表字段 = 值 满意条件:
eg: update user set id = 1 where name = 'li';
update user set id = 1 where name = "li" and passwd = "123";
update user set id = 2 where name = "li" or name = "zhao";
删除表中数据:
delete from 表名 满意条件:
eg:delete from user ; ///删除表中所有数据
delete from user where id = 1; ///删除id=1 的数据;
delete from user where id =1 and name = "zhang";
delete from user where id = 1 or id = 2;
数据的导出: