Tsql 在T-SQL中可能使用更优雅的语句而不是sub-select
我有以下代码,用于计算唯一客户[ClientWHID]以及这些客户在进入特定医院[Program]12个月后无家可归的天数, 请看下面 我想知道,是否有更优雅的方式来编写这段代码? 例如,要用CASE语句替换我在括号中的sub select cte? 还是在这种情况下不可能Tsql 在T-SQL中可能使用更优雅的语句而不是sub-select,tsql,subquery,case,Tsql,Subquery,Case,我有以下代码,用于计算唯一客户[ClientWHID]以及这些客户在进入特定医院[Program]12个月后无家可归的天数, 请看下面 我想知道,是否有更优雅的方式来编写这段代码? 例如,要用CASE语句替换我在括号中的sub select cte? 还是在这种情况下不可能 DECLARE @BOP date = '07/01/2019' DECLARE @EOP date = '06/30/2020' DECLARE @EHRProgramWHID int = -
DECLARE @BOP date = '07/01/2019'
DECLARE @EOP date = '06/30/2020'
DECLARE @EHRProgramWHID int = -1; -- 54500457 = SM AOT; 54200471 = SM FSP
SELECT
cte.[EHRProgramWHID]
,cte.[ProgramName]
,COUNT( DISTINCT cte.[ClientWHID]) AS [# Homeless Clients 12 Mo after Enrollment]
,SUM (cte.[# Homeless Days]) AS [# Homeless Days 12 Mo after Enrollment]
FROM
(
SELECT
epi.[EHRProgramWHID]
,prg.[ProgramName]
,epi.[Domain]
,epi.[Subdomain]
,epi.[ClientWHID]
,epi.[BeginDate]
,epi.[EndDate]
,IIF(epi.[BeginDate] < @BOP, @BOP, epi.[BeginDate]) AS [Upd_BeginDate]
,IIF(epi.[EndDate] > @EOP, @EOP, epi.[EndDate]) AS [Upd_EndDate]
,DATEDIFF(day, IIF(epi.[BeginDate] < @BOP, @BOP, epi.[BeginDate]),
IIF(epi.[EndDate] > @EOP, @EOP, epi.[EndDate])) AS [# Homeless Days]
FROM
WHMHSA.[DomainStatusEpisodes] epi
INNER JOIN [Dimension].[Program] prg ON epi.[EHRProgramWHID] = prg.[WHID]
WHERE
NOT( ( (epi.BeginDate < @BOP) AND (epi.EndDate < @BOP) ) OR
( (epi.BeginDate > @EOP) AND (epi.EndDate > @EOP) ) )
AND (epi.Domain = 'Residential')
AND (epi.Subdomain = 'Homeless')
AND (epi.EHRProgramWHID IN (54500457, 54200471))
) cte
GROUP BY
cte.[EHRProgramWHID]
,cte.[ProgramName]
ORDER BY
cte.[ProgramName]
因为除了EHRProgramWHID、ProgramName、ClientWHID之外,您不使用CTE部件的任何列,所以不需要返回它们 如果没有样本数据,我无法检查这一点,但请尝试:
DECLARE @BOP date = '07/01/2019'
DECLARE @EOP date = '06/30/2020'
DECLARE @EHRProgramWHID int = -1; -- 54500457 = SM AOT; 54200471 = SM FSP
SELECT
epi.[EHRProgramWHID]
,prg.[ProgramName]
,COUNT( DISTINCT epi.[ClientWHID]) AS [# Homeless Clients 12 Mo after Enrollment]
,SUM (DATEDIFF(day, IIF(epi.[BeginDate] < @BOP, @BOP, epi.[BeginDate]),
IIF(epi.[EndDate] > @EOP, @EOP, epi.[EndDate]))) AS [# Homeless Days 12 Mo after Enrollment]
FROM WHMHSA.[DomainStatusEpisodes] epi
INNER JOIN [Dimension].[Program] prg ON epi.[EHRProgramWHID] = prg.[WHID]
WHERE
NOT( ( (epi.BeginDate < @BOP) AND (epi.EndDate < @BOP) ) OR
( (epi.BeginDate > @EOP) AND (epi.EndDate > @EOP) ) )
AND (epi.Domain = 'Residential')
AND (epi.Subdomain = 'Homeless')
AND (epi.EHRProgramWHID IN (54500457, 54200471))
GROUP BY
epi.[EHRProgramWHID]
,prg.[ProgramName]
ORDER BY
prg.[ProgramName]