有没有办法在一种语法中选择具有不同子查询的两个计数？

Question

基本上我想得到两个计数。第一个计数是记录数。第二个计数是包含数据的记录数。这两个计数来自名为调查的表，其中没有所有的州名。所以我将其与其他表UsState一起加入以获取所有州名。我把语法放在一起但是我收到了一个错误。

SELECT
Name as State,
count (*)from NamrsFrozen2017.Investigation2017 where FiscalYear = 2017 AND StateName in (SELECT distinct StateName FROM [NamrsFrozen2017].[Investigation2017] WHERE (not ReportDate = '' ))[Report Date Records],
count (*) from NamrsFrozen2017.Investigation2017 WHERE FiscalYear = 2017 AND ReportDate != '' AND StateName in (SELECT distinct StateName FROM [NamrsFrozen2017].[Investigation2017] WHERE (not ReportDate = '' ))[Report Date Records with Data]
From
(SELECT DISTINCT Name FROM NamrsFullDw.UsState) s
LEFT JOIN NamrsFrozen2017.Investigation2017 c ON s.Name = c.StateName AND  c.FiscalYear = 2017
  GROUP BY Name
  Order by Name

Answer 1

一些相关的子查询可以帮助您。它们看起来像是内联选择，但使用对内联查询之外的表的引用。像这样：

SELECT 
   Name as State,
   (SELECT COUNT(*) 
    FROM NamrsFrozen2017.Investigation2017 
    --I would think you want to view count of records for the current state, and not ALL states
    -- and not ALL states. So filter like this:
    WHERE FiscalYear = 2017 AND StateName = s.Name -- <-Correlated
    --Don't need a full list, like you had before
    -- (SELECT distinct StateName FROM [NamrsFrozen2017].[Investigation2017] WHERE (not ReportDate = '' ))
   ) AS [Report Date Records],
   (SELECT COUNT(*) 
    FROM NamrsFrozen2017.Investigation2017 
    WHERE FiscalYear = 2017 AND StateName = s.Name -- <- correlated
        AND ReportDate != '' --or maybe ReportDate IS NOT NULL            
    --Don't need to query the full table after correlating this to your FROM clause
    --  in (SELECT distinct StateName FROM [NamrsFrozen2017].[Investigation2017] WHERE (not ReportDate = '' ))
   ) AS [Report Date Records with Data]
FROM
   (SELECT DISTINCT Name FROM NamrsFullDw.UsState) s
   LEFT JOIN NamrsFrozen2017.Investigation2017 c 
        ON s.Name = c.StateName AND c.FiscalYear = 2017
GROUP BY s.Name
ORDER BY s.Name

这可能会更加优化，但我不熟悉您的数据，或者清楚您要使用原始查询完成什么。

Answer 2

评论太久了。

您获得的语法错误是因为您的内联子查询格式不正确。你不能从COUNT(*)函数开始;他们每个人都需要完全形成SELECT声明。然后每个都需要用括号括起来。

这是您的查询应该是什么样子。

SELECT
  Name AS State
 ,(
    SELECT
      COUNT(*)
    FROM
      NamrsFrozen2017.Investigation2017
    WHERE
      FiscalYear = 2017
      AND StateName IN
          (
            SELECT DISTINCT StateName
            FROM NamrsFrozen2017.Investigation2017
            WHERE ReportDate <> ''
          )
  ) AS [Report Date Records]
 ,(
    SELECT
      COUNT(*)
    FROM
      NamrsFrozen2017.Investigation2017
    WHERE
      FiscalYear = 2017
      AND ReportDate != ''
      AND StateName IN
          (
            SELECT DISTINCT StateName
            FROM NamrsFrozen2017.Investigation2017
            WHERE (NOT ReportDate = '')
          )
  ) AS [Report Date Records with Data]
FROM
  (SELECT DISTINCT Name FROM NamrsFullDw.UsState) AS s
LEFT JOIN
  NamrsFrozen2017.Investigation2017 AS c
    ON
    s.Name = c.StateName
      AND c.FiscalYear = 2017
GROUP BY
  Name
ORDER BY
  Name;

这里有一个次要问题，即这个查询是否会完成你期望它做的事情。对于Larnu在评论中的观点，聚合函数在不同情况下处理NULL的方式不同。但是如果没有要测试的样本数据，我无法判断这个功能版本的查询是否会返回您想要的内容。