我想判断poi_Equipement表(关系表)是否与数据表中的数据对应(即双向判断)
检测到WC(在PoI_Equipement中)是额外的(因为它不在数据表中)，并且wine 店不在Poi_Equipement中，所以与数据表相比它是不存在的
我不明白为什么要用拉奎特，除了他只回答我住的wine 店. 我要他回答我wine 店和厕所的问题.
select object from data where subject = 'url1'
except
select subject from poi_equipement inner join equipement on poi_equipement.equipement_id = equipement.id;
理想情况下，我想知道我在位置设备、数据或两个表中有什么不同
完全的外连接就可以了
with params as (
select 'url1' as subject),
data_object as (
select d.object
from data d
join params prm
on d.subject = prm.subject),
equipment_subject as (
select e.subject
from poi_equipement pe
join poi p
on pe.poi_id = p.id
join equipement e
on pe.equipement_id = e.id
join params prm
on p.id_url = prm.subject)
select d.object as data,
e.subject as poi_equipment
from data_object d
full outer
join equipment_subject e
on d.object = e.subject
where d.object is null
or e.subject is null;
结果:
data |poi_equipment|
-----+-------------+
hotel| |
|wc |
如果您需要查看哪一项同时出现在两个位置，则可以删除where条款.