如何检查其中一个索赔人是否具有状态 0 并根据该状态分配索赔状态答案

【问题标题】：how to check whether one of Claimants have Status 0 and assign Claim Status based on that如何检查其中一个索赔人是否具有状态 0 并根据该状态分配索赔状态
【发布时间】：2019-04-01 23:01:33
【问题描述】：

每个声明可以有多个声明人。如果这些声明中至少有一个拥有ClaimantStatus = 0，则认为声明为'Open'

所以我需要检索关于 Claim Level（不是 Claimants）的数据并创建列 ClaimStatus 来指示 Claim 是 Open 还是 Closed。

对于每个ClaimID，我需要检查是否至少有一个索赔人有ClaimantStatus = 0（打开），如果这是真的，那么列ClaimStatus应该是='Open'，否则应该是=@987654332 @

 declare @ClaimsTable table (ClaimID varchar(20))
 insert into @ClaimsTable values ('Claim1'),
                                 ('Claim2'),
                                 ('Claim3'),
                                 ('Claim4')

declare @ClaimantsTable table (ClaimID varchar(20),  ClaimantName varchar(50), ClaimantStatus int)
insert into @ClaimantsTable values ('Claim1','Claimant1',1),
                                   ('Claim1','Claimant2',0),
                                   ('Claim1','Claimant3',1),
                                   ('Claim2','Claimant2',0),
                                   ('Claim3','Claimant1',1),
                                   ('Claim3','Claimant2',1),
                                   ('Claim3','Claimant3',1),
                                   ('Claim4','Claimant1',0),
                                   ('Claim4','Claimant2',0)
--select * from @ClaimantsTable

select ClaimID,
        (select count (ClaimantName) from @ClaimantsTable ct where ct.ClaimID = c.ClaimID) as NumberOfClaimants,
    --below statement does not work correctly
        (select top 1 case when ClaimantStatus in (0) then 'Open' Else 'Closed' end as t from @ClaimantsTable ct where ct.ClaimID = c.ClaimID) as ClaimStatus
from @ClaimsTable c

正确答案应该是这样的：

【问题讨论】：

标签： sql sql-server tsql sql-server-2012

【解决方案1】：

看起来一个简单的GROUP BY 就足够了。如果至少有一个Claimant 的 ClaimantStatus = 0，则Claim 处于打开状态，我们可以使用MIN 来确定这一点。这里我们依赖 ClaimantStatus 只有 0 和 1 值。

SELECT
    Claims.ClaimID
    ,COUNT(*) AS NumberOfClaimants
    ,CASE WHEN MIN(Claimants.ClaimantStatus) = 0 
        THEN 'Open' 
        ELSE 'Closed' 
    END AS ClaimStatus
FROM
    @ClaimsTable AS Claims
    INNER JOIN @ClaimantsTable AS Claimants ON Claimants.ClaimID = Claims.ClaimID
GROUP BY
    Claims.ClaimID
ORDER BY
    Claims.ClaimID;

【讨论】：

非常简单的方法！谢谢

【解决方案2】：

我认为使用 Exists 是您正在寻找的内容

select ClaimID,
    (select count (ClaimantName) from @ClaimantsTable ct where ct.ClaimID = c.ClaimID) as NumberOfClaimants,
    CASE WHEN EXISTS(SELECT 1 
                    FROM @ClaimantsTable AS claimant 
                    WHERE claimant.ClaimID = c.ClaimID
                        AND claimant.ClaimantStatus = 0) 
        THEN 'Open' 
        ELSE 'Closed' END AS claimStatus
from @ClaimsTable c

根据您的情况，您还可以考虑分组查询。通过不需要对计数和状态进行两次单独的查找，这可以更有效。这确实要求每个索赔至少有 1 个索赔人。

SELECT
    claim.ClaimId
    ,COUNT(*) AS NumberOfClaimants
    ,CASE WHEN SUM(CASE WHEN claimant.ClaimantStatus = 0 THEN 1 ELSE 0 END) > 0 THEN 'Open' ELSE 'Closed' END AS claimStatus
FROM
    @ClaimsTable AS claim
    INNER JOIN @ClaimantsTable AS claimant
        ON claim.ClaimID = claimant.ClaimID
GROUP BY
    claim.ClaimID

【讨论】：

完美。谢谢！