不用inner join，直接用
update tablea，tableb set tablea. follow_up_user=tableb.user_code where tablea. customer_code=tableb. customer_code
  
【 在 jiangbojava (jiangbojava) 的大作中提到: 】
:  update tableA s
:      inner join (SELECT ci.customer_code, ci.user_code from tableB ci) ca on (ca.customer_code = s.customer_code)
:  set s.follow_up_user = ca.user_code;
:  
--
FROM 223.104.42.*