MySQL---Subquery returns more than 1 row

例如：

select * from user_facility 
where user_id = 60040012 
and facility_id =
(select facility_id from scene_facility_room where room_id = 5);

会报错 Subquery returns more than 1 row

原因：

因为使用的字段使用的=，只符合select语句只查出一条记录的情况。
如果查出的记录是多条记录，这时上述语句会报Subquery returns more than 1 row

解决：

有两种方法

1. 语句中的 = 换成 in，如下：

select * from user_facility 
where user_id = 60040012 
and facility_id in
(select facility_id from scene_facility_room where room_id = 5);

2. 语句中 = 后面加 any，如下：

select * from user_facility 
where user_id = 60040012 
and facility_id =
any (select facility_id from scene_facility_room where room_id = 5);