如何使用JOIN连接两个表

Question

能帮我如何在单个表中连接两个查询吗？>

发光细节表：

select 
    mac_id, round(sum(luminary_count::int * wattage::int)::numeric/100, 2) as rated_power 
from 
    luminary_details AS A
join 
    geo_light as gl on A.mac_id = gl.id 
group by
    A.mac_id
// lastupdated_all

select mac_id, (tactivep::numeric)
from lastupdated_all AS A
join geo_light as gl on A.mac_id = gl.id 
group by A.mac_id

[能帮我如何在单个表的发光细节表中加入两个查询：从...中选择mac_id，round（sum（luminary_count :: int * wattage :: int）:: numeric / 100，2）作为rated_power ...

Answer 1

您可以使用geo_ligth作为主表，并以子选择..的方式将2个查询左联接为..通过id = mac_id联接