执行 T-SQL GROUP BY 子句时遇到问题

Question

在我陷入抑郁之前有人帮助我。

我正在创建一个简单的许可投票系统。收到许可证后，必须由委员会批准或拒绝。该委员会由 5 名成员组成，投票过程基于多数票（意味着收到的每个申请都需要 3 名或更多委员会成员的批准/拒绝。例如 如果 3 名或更多成员投票批准该申请被称为“批准”，如果 3 个或更多成员投票拒绝，则该申请被称为“被拒绝”）。

这个想法是始终需要 3 个多数票来确定应用程序的状态。如果委员会的所有成员都没有投票或每个状态（批准或拒绝）的投票数少于 3，则应用程序被称为 “待处理” 例如，如果 2 个成员批准并且2 个拒绝 OR 2 个批准和 1 个拒绝 OR 1 个批准和 2 个拒绝 OR 1 个批准和 1 个拒绝 OR 仅限2 个批准或只有 2 个拒绝

这是正在处理的一张表的结构

CREATE TABLE [CommitteeApproval](
[CommitteeApprovalID] [int] IDENTITY(1,1) NOT NULL,
[LicenceApplicationID] [int] NOT NULL,
[UserID] [int] NOT NULL,
[ActionDate] [date] NULL,
[CommitteeApprovalStatusID] [int] NOT NULL)

[CommitteeApproval] 是主键，而 [LicenceApplicationID] 、[CommitteeApprovalStatusID] 和 [UserID]是它们各自表的外键。

[CommitteeApprovalStatus] 表（CommitteeApprovalStatus 为主键）

   CommitteeApprovalStatusID      CommitteeApprovalStatusName
    1                             Approve
    2                             Reject

[CommitteeApproval] 表格包含

LicenceApplicationID UserID ActionDate  CommitteeApprovalStatusID
4173                  37    2013-12-17         2
4173                  36    2013-12-17         1
4173                  6     2013-12-17         1
4173                  7     2013-12-17         1
4174                  37    2013-12-17         1
4174                  36    2013-12-17         2
4174                  7     2013-12-17         2
4174                  6     2013-12-17         2
4174                  38    2013-12-17         2
4176                  38    2013-12-17         2
4177                  7     2013-12-17         2
4179                  36    2013-12-17         1
4179                  38    2013-12-17         2

我想返回每个许可证申请的 CommitteeApprovalStatus 编号。 例如：对于LicenceApplication4174，4个成员被拒绝，2个成员被批准，所以申请被称为“被拒绝”

我使用以下查询向用户显示被拒绝的应用程序列表

SELECT LicenceApplicationID ,CommitteeApprovalStatusID ,COUNT(UserID) AS votes
  FROM CommitteeApproval
  WHERE CommitteeApprovalStatusID=2
  GROUP BY LicenceApplicationID, CommitteeApprovalStatusID
  HAVING COUNT(UserID) >= 3

我还成功检索了已批准的查询列表，其中包含类似的查询，但替换为

WHERE CommitteeApprovalStatusID=1

现在，当我尝试检索“待处理”应用程序列表时，就会出现问题。

1. 我无法捕获 2 个成员批准和 2 个成员拒绝、1 个成员批准和 1 个成员拒绝、2 个成员批准但没有或 1 个成员被拒绝、3 个成员被拒绝和 1 或 2 个成员批准、2成员被拒绝，3 个成员被批准。

2. 我一次只能捕获一种类型的申请，例如 WHERE CommitteeApprovalStatusID=2 或 1，而我想捕获所有不符合条件的申请。

我写的查询是：

 SELECT LicenceApplicationID, COUNT(UserID) AS votes 
 FROM CommitteeApproval   
 WHERE CommitteeApprovalStatusID=1 
 GROUP BY LicenceApplicationID   
 HAVING COUNT(UserID) < 3

这并没有多大帮助，因为我仍然需要用

写另一个

WHERE CommitteeApprovalStatusID=2

它仍然无法捕获问题 1 中的结果。有没有办法通过一个查询显示所有“待处理”结果？？

Answer 1

我对可读性的尝试：

WITH votes AS (
  SELECT
    LicenceApplicationID,
    CommitteeApprovalStatusName Vote
  FROM CommitteeApproval A
  INNER JOIN CommitteeApprovalStatus S ON 
    S.CommitteeApprovalStatusID = A.CommitteeApprovalStatusID
)
SELECT
  LicenceApplicationID,
  Approve,
  Reject,
  CASE
    WHEN  Approve >= 3 THEN 'Approved'
    WHEN  Reject  >= 3 THEN 'Rejected'
    ELSE 'Pending'
  END AS VoteStatus
FROM votes
PIVOT(COUNT(Vote) FOR Vote IN (Approve,Reject)) P

Answer 2

试试这个：

 SELECT LicenceApplicationID, COUNT(UserID) AS votes, 
 CASE  WHEN CommitteeApprovalStatusID = 1 THEN 'Aprove' ELSE 'Rejected' END AS Status
 FROM CommitteeApproval   
 WHERE CommitteeApprovalStatusID in (1, 2) 
 GROUP BY LicenceApplicationID, CommitteeApprovalStatusID    
 HAVING COUNT(UserID) < 3

Answer 3

试试这个查询

select 
  * 
from 
  (select 
    LicenceApplicationID,
    sum(case when 
          CommitteeApprovalStatusID=1 then 1 
        else 0 end) as pass,
    sum(case when 
          CommitteeApprovalStatusID=2 then 1 
        else 0 end) as fail
    from 
        tbl
    group by 
        LicenceApplicationID
  )tbl 
where 
  pass < 3 and 
  fail < 3

Fiddle

| LICENCEAPPLICATIONID | PASS | FAIL |
|----------------------|------|------|
|                 4176 |    0 |    1 |
|                 4177 |    0 |    1 |
|                 4179 |    1 |    1 |

Answer 4

试试这个。

(SELECT LicenceApplicationID, COUNT(UserID) As "Votes"
FROM CommitteeApproval
WHERE CommitteeApprovalStatusID = 2) B

SELECT LicenceApplicationID,
CASE 
WHEN A.Votes > 2 THEN "Approved"
WHEN B.Votes >2 THEN  "Rejected"
ELSE "Pending"

END AS "Status"

FROM 

(SELECT LicenceApplicationID, COUNT(UserID) AS "Votes"
FROM CommitteeApproval
WHERE CommitteeApprovalStatusID = 1
GROUP BY LicenceApplicationID ) A 

FULL OUTER JOIN

(SELECT LicenceApplicationID, COUNT(UserID) AS "Votes"
FROM CommitteeApproval
WHERE CommitteeApprovalStatusID = 2
GROUP BY LicenceApplicationID ) B

ON A.LicenceApplicationID = B.LicenceApplicationID