SQL差集

Question

我會怎麼做在SQL如下：

select distinct(territory_id) from main_territorypricing 

"minus" 

select distinct(territory_id) from main_territorypricing where store_url is not null 

基本上，我想包含在未包含在第二行的頂線所有territory_id秒。

Answer 1

如果你想要做的，你說：

select distinct territory_id 
from main_territorypricing 
where territory_id not in (
    select territory_id from main_territorypricing where store_url is not null 
    ) 

但根據你所描述什麼邏輯，更容易的解決方案是：

select territory_id 
    from main_territorypricing 
    where store_url is null 

這是，前提是你只有這兩個字段（territory_id和store_url），行是唯一的。

否則，還有另一個棘手的溶液：

select territory_id 
from main_territorypricing 
group by territory_id 
having (max(store_url) is null) 

Answer 2

select distinct(territory_id) from main_territorypricing 
where 
    territory_id in 
     (select territory_id from main_territorypricing) 
and territory_id not in 
    (select territory_id from main_territorypricing where store_url is not null)