select *from userinfo
insert into userinfo(userName,userPass)
values('admin','123456')
update userinfo
set userPass='222222'
where(userName='admin')
你的语句的执行顺序是:先查询,再写入,最后更新,把查询语句放到最后面,如:
insert into userinfo(userName,userPass)
values('admin','123456')
update userinfo
set userPass='222222'
where(userName='admin')
select *from userinfo