2つのサブクエリのSQL MAX値

Question

2つのクエリがあり、そのうちの2つのクエリの最大値を取得したいとします。

MAX((SELECT COUNT(p.[ItemID]) FROM [dbo].[Table] p WHERE HasHuman=0), 
     (SELECT COUNT(p.[ItemID]) FROM [dbo].[Table] p WHERE HasHuman=1)) 

Answer 1

あなたは、単一のクエリで両方の結果を計算して、TOPを適用することができます。

select top 1 
    HasHuman, 
    COUNT(p.[ItemID]) as cnt 
from [dbo].[Table] 
group by HasHuman 
order by cnt desc 

Answer 2

SELECT MAX(RC) 
FROM (SELECT COUNT(p.ItemID) AS RC FROM dbo.[Table] 
     WHERE HasHuman=0 
     UNION 
     SELECT COUNT(p.ItemID) AS RC FROM dbo.[Table] 
     WHERE HasHuman=1 
     ) A 

Answer 3

あなたも、単一のクエリでこれを行うことができます：

SELECT 
    CASE WHEN SUM(CASE WHEN HasHuman=0 THEN 1 ELSE 0 END) > 
       SUM(CASE WHEN HasHuman=1 THEN 1 ELSE 0 END) 
     THEN SUM(CASE WHEN HasHuman=0 THEN 1 ELSE 0 END) 
     ELSE SUM(CASE WHEN HasHuman=1 THEN 1 ELSE 0 END) END 
FROM [dbo].[Table] 
WHERE ItemID IS NOT NULL -- you were not counting NULLs