mysql - 执行多重选择时，错误子查询返回大于 1

Question

我想在一个查询中使用不同的条件进行多项选择。但不知何故我陷入了这个问题。有什么想法吗？

SELECT
    (select io_link_event_names.name from doors left join controller_devices on doors.iid = controller_devices.iid left join events on controller_devices.mac = events.mac left join io_link_event_names on events.iolinkerid = io_link_event_names.extra where events.iolinkerid = "9000;1") AS forced,
    (select doors.name FROM doors) AS doorname

错误 #1242 - 子查询返回超过 1 行

Answer 1

考虑一下

SELECT d.[forced], doors.name as doorname
from doors
left join (
select  controller_devices.iid, io_link_event_names.name as [forced]
from events
inner join controller_devices on controller_devices.mac = events.mac 
inner join io_link_event_names on events.iolinkerid = io_link_event_names.extra 
where events.iolinkerid = "9000;1"
) as d on d.iid = doors.iid