我有一个病人可以接受多种服务的情况。这些服务可能有重叠的日期,并且可能会有空白和孤岛。我正在尝试编写一个查询,以显示患者正在接受某种服务的连续时间。
表如下:
CREATE TABLE #tt
(Patient VARCHAR(10), StartDate DATETIME, EndDate DATETIME)
INSERT INTO #tt
VALUES
('Smith', '2014-04-13', '2014-06-04'),
('Smith', '2014-05-07', '2014-05-08'),
('Smith', '2014-06-21', '2014-09-19'),
('Smith', '2014-08-27', '2014-08-27'),
('Smith', '2014-08-28', '2014-09-19'),
('Smith', '2014-10-30', '2014-12-16'),
('Smith', '2015-05-21', '2015-07-03'),
('Smith', '2015-05-22', '2015-07-03'),
('Smith', '2015-05-26', '2015-11-30'),
('Smith', '2015-06-25', '2016-06-08'),
('Smith', '2015-07-22', '2015-10-22'),
('Smith', '2016-08-11', '2016-09-02'),
('Smith', '2017-06-02', '2050-01-01'),
('Smith', '2017-12-22', '2017-12-22'),
('Smith', '2018-03-25', '2018-06-30')
如您所见,许多日期重叠。最终,我希望看到以下结果,这些结果将显示患者接受至少一项服务的日期,例如:
Patient |StartDate |EndDate
--------------------------------------
Smith |2014-04-13 |2016-06-04
Smith |2014-06-21 |2014-09-19
Smith |2014-10-30 |2014-12-16
Smith |2015-05-21 |2016-06-08
Smith |2016-08-11 |2016-09-02
Smith |2017-06-02 |2050-01-01
通过查看各种空白和孤岛SQL代码,我感到一头雾水。我已经开始使用此CTE,但是显然它没有用,如果我想要这个,我可以简单地使用SELECT PHN,Min(StartDate),MAX(EndDate)
WITH HCC_PAT
AS
(
SELECT DISTINCT
PHN,
StartDate,
EndDate,
MIN (StartDate) OVER ( PARTITION BY PHN ORDER BY StartDate
ROWS BETWEEN UNBOUNDED PRECEDING AND 1 PRECEDING) AS PreviousStartDate,
MAX (EndDate) OVER ( PARTITION BY PHN ORDER BY EndDate
ROWS BETWEEN UNBOUNDED PRECEDING AND 1 PRECEDING) AS PreviousEndDate
FROM #tt)
SELECT DISTINCT --hcc_Pat.HCCClientKey,
hcc_pat.PHN,
hcc_pat.StartDate,
ISNULL (LEAD (PreviousEndDate) OVER (PARTITION BY PHN ORDER BY ENDDATE), 'January 1, 2050') AS EndDate
FROM HCC_PAT
WHERE PreviousEndDate > StartDate
AND (StartDate < PreviousStartDate OR PreviousStartDate IS NULL)
在此感谢您的帮助
答案 0 :(得分:1)
一种方法将日期散布开来,以指示服务是开始还是结束。然后可以使用指标的累加总和来定义不同的组-累加总和中的零值是一个周期结束的时间。
最后一步是聚合:
with d as (
select patient, startdate as dte, 1 as inc from tt
union all
select patient, enddate as dte, -1 as inc from tt
),
dd as (
select patient, dte, sum(sum(inc)) over (order by dte) as cume_inc
from d
group by patient, dte
),
ddd as (
select dd.*, sum(case when cume_inc = 0 then 1 else 0 end) over (partition by patient order by dte desc) as grp
from dd
)
select patient, min(dte) as startdate, max(dte) as enddate
from ddd
group by grp;
Here是一个SQL提琴。