将两个 SQL 查询结果合并为一个结果答案

【问题标题】：Merge two SQL query results into one result将两个 SQL 查询结果合并为一个结果
【发布时间】：2015-06-10 08:57:20
【问题描述】：

我有如下查询：

SELECT COUNT(*) AS AppleSupports 
FROM VendorItemPricing 
WHERE VendorName = 'Apple'

SELECT COUNT(*) AS HpSupports 
FROM VendorItemPricing 
WHERE VendorName = 'HP'

上面的查询给我的结果如下：

AppleSupports
63

HpSupports
387

如何让我的查询在一行中得到如下所示的结果？

AppleSupports    HpSupports
63               387

【问题讨论】：

标签： sql sql-server sql-server-2008 sql-server-2012

【解决方案1】：

Select   Sum(Case When vp.VendorName = 'Apple' Then 1 Else 0 End) As AppleSupports
        ,Sum(Case When vp.VendorName = 'HP' Then 1 Else 0 End) As HpSupports
From    VendorItemPricing As vp With (Nolock)
Where   vp.VendorName In ('Apple','HP')

【讨论】：

【解决方案2】：

在你的选择语句中使用子查询：

SELECT
(select count(*) from VendorItemPricing where VendorName = 'Apple') as AppleSupports,
(select count(*) from VendorItemPricing where VendorName = 'HP') AS HpSupports

【讨论】：

【解决方案3】：

理想情况下你应该这样做，

select [Apple] as AppleSupport, [Hp] as HpSupport from (
    select VendorName from VendorItemPricing
) as sourcetable
pivot 
( count(VendorName)
 for VendorName in ([Apple],[Hp])
 )  as pivottable

您还可以为结果集中的更多列添加值（如 Apple、Hp）

【讨论】：

【解决方案4】：

试试这个。

SELECT SUM(AppleSupports) AS AppleSupports, SUM(HpSupports) AS HpSupports
FROM 
(
    SELECT CASE WHEN VendorName = 'Apple' 
               THEN COUNT( *) END AS AppleSupports,
          CASE WHEN VendorName = 'HP' 
               THEN COUNT(*) END AS HpSupports
    FROM VendorItemPricing 
    GROUP BY VendorName
) AS A

【讨论】：

【解决方案5】：

它需要一个简单的查询连接。试试这个：

select * from 
(select  count(*) as AppleSupports from VendorItemPricing where VendorName = 'Apple'),
(select  count(*) as HpSupports from VendorItemPricing where VendorName = 'HP')

【讨论】：

【解决方案6】：

最简单的方法是：

SELECT 
    COUNT(CASE WHEN VendorName = 'Apple' Then 1 End) As AppleSupports,
    COUNT(CASE WHEN VendorName = 'HP'    THEN 1 End) As HpSupports
FROM
    VendorItemPricing

【讨论】：