在特定时间范围内与事件的关系划分

Question

我有我的表（cte）定义和结果集here

CTE可能看起来很奇怪，但已经过测试，并以我发现的最有效的方式返回正确的结果。以下查询将查找同时服用两种或更多种药物的人员ID（patid）。目前，该查询起作用，因为它返回同时服用两种药物但不同时服用两种药物的人的patID。一种fillDate药物在另一种药物scriptEndDate之前下降，表明服用这两种药物。所以

您可以在此部分结果集中看到第18行scriptFillDate为2009-07-19，它位于第2行相同patID的fillDate和scriptEndDate之间。我需要添加什么约束才能过滤掉这些不需要的结果？

--PatientDrugList is a CTE because eventually parameters might be passed to it
--to alter the selection population
;with PatientDrugList(patid, filldate, scriptEndDate,drugName,strength)
as
(
    select rx.patid,rx.fillDate,rx.scriptEndDate,rx.drugName,rx.strength
        from rx
),
--the row constructor here will eventually be parameters for a stored procedure
DrugList (drugName)
as
(
    select x.drugName
        from (values ('concerta'),('fentanyl'))
        as x(drugName)
        where x.drugName is not null
)


    --the row number here is so that I can find the largest date range
    --(the largest datediff means the person was on a given drug for a larger
    --amount of time.  obviously not a optimal solution
     --celko inspired relational division!
     select distinct row_number() over(partition by pd.patid, drugname order by datediff(day,pd.fillDate,pd.scriptEndDate)desc)  as rn
     ,pd.patid
    ,pd.drugname
    ,pd.fillDate
    ,pd.scriptEndDate
    from PatientDrugList as pd
    where not exists
    (select * from DrugList 
    where not exists
    (select * from PatientDrugList as pd2
    where(pd.patid=pd2.patid)
    and (pd2.drugName = DrugList.drugName)))
    and exists 
    (select * 
        from DrugList
        where DrugList.drugName=pd.drugName
    )
    group by pd.patid, pd.drugName,pd.filldate,pd.scriptEndDate

Answer 1

将原始查询包装到CTE中，或者更好的是，为了查询计划和结果的性能，稳定性，将其存储到临时表中。

以下查询（假设CTE选项）将为您提供两种药物的重叠时间。

;with tmp as (
   .. your query producing the columns shown ..
)
select *
  from tmp a
  join tmp b on a.patid = b.patid and a.drugname <> b.drugname
 where a.filldate < b.scriptenddate
   and b.filldate < a.scriptenddate;