SQL查詢是否出現更多，一旦在一個表中顯示其他表數據

Question

當OwnerID在屬性中出現多次時，我試圖從所有者獲取OwnerID，FName，LName。這是我嘗試過，但即時通訊很新的SQL，所以我不知道這是否甚至接近。

Select OwnerID, FName, LName 
From Owner 
Where OwnerID = (Select OwnerID 
       From Property 
       GROUP BY OwnerID 
       HAVING Count(*) >=2) 

Answer 1

您是不是要找：

Select OwnerID, FName, LName 
From Owner 
Where OwnerID In (Select OwnerID 
       From Property 
       Group By OwnerID 
       Having Count(OwnerId) >= 2) 

但如果你試圖讓誰擁有超過1個物業全體業主，即假設一個屬性始終只有一個老闆，這並不總是在現實世界中的情況。

Answer 2

您可以使用運營商像@米奇小麥答案，或使用EXISTS：

Select OwnerID, FName, LName 
From Owner a 
Where EXISTS (Select b.OwnerID 
       From Property b 
       WHERE a.OwnerID = b.OwnerID 
       Group By b.OwnerID 
       Having Count(b.OwnerId) >= 2) 

Answer 3

的服務表現，我會做

Select OwnerID, FName, LName 
From Owner a 
Where EXISTS (Select * 
      From Property b 
      WHERE a.OwnerID = b.OwnerID 
      Group By b.OwnerID 
      Having Count(*) >= 2)