select company_name from company where company.company_id=user.user_companyid
如果我修改company表中的数据,如何保证原先的数据,1改全改?
select company_name form company where company_id = (select user_companyid form user where user_id = 所要得id)另外一种 select c.company_name form company c,user u where u.user_id = 所要得id and u.company_id = c.company_id
select c.company_name form company c,user u where u.user_id = 所要得id and u.company_id = c.company_id