使用子查询SQL Server 2008连接两个子查询或查询

Question

怪物编辑:查询现在将运行但返回不正确的答案.添加了粗略的架构.PatientID不是tblPatientVisits表中的主键,因为同一个patientID可以多次出现.

列出每个县名称,但每个县名称(s.countyName)和count(t.countyname)为1

PatientVisits   
PatientID   int
PatientState    varchar(2)
patientCounty   varchar(3)
visitNumber int - PK

tblStateCounties    
CPK stateCode   varchar(2)
CPK countyCode  varchar(3)
countyName  varchar(25)


SELECT t.countyName,
    count(t.countyName) as reAdmits ,count(s.countyName) as totalVisits
FROM (
    SELECT countyName,count(countyName) AS readmitCounts
    FROM (
        SELECT tblPatient.patientID
            ,tblStateCounties.countyName
        FROM tblPatient
        INNER JOIN tblPatientVisits
            ON tblPatient.patientID = tblPatientVisits.patientID
        INNER JOIN tblStateCounties
            ON tblPatientVisits.patientState = tblStateCounties.stateCode
                AND tblPatientVisits.patientCounty = tblStateCounties.countyCode
        GROUP BY tblPatient.patientID
            ,tblStateCounties.stateCode
            ,tblStateCounties.countyName
        HAVING (COUNT(tblPatient.patientID) > 1)
            AND (tblStateCounties.stateCode = '21')
        ) t
    GROUP BY countyname
    ) t
INNER JOIN (
    SELECT countyName
    FROM (
        SELECT tblStateCounties.countyName
            ,COUNT(tblStateCounties.countyName) AS counts
        FROM tblPatient
        INNER JOIN tblPatientVisits
            ON tblPatient.patientID = tblPatientVisits.patientID
        INNER JOIN tblStateCounties
            ON tblPatientVisits.patientState = tblStateCounties.stateCode
                AND tblPatientVisits.patientCounty = tblStateCounties.countyCode
        WHERE (tblStateCounties.stateCode = '21')
        GROUP BY tblStateCounties.countyName
        ) z
    ) s
    ON s.countyName = t.countyName
    group by s.countyname, t.countyname

编辑:我有一个现在运行的查询,但它返回

Answer 1

很难说没有样本数据和期望的结果,但也许这就是你所追求的？

;WITH x AS 
(
  SELECT c.CountyName, v.patientCounty, v.patientState, p.patientID
    FROM dbo.tblPatient AS p
    INNER JOIN dbo.tblPatientVisits AS v
    ON p.patientID = v.patientID 
    INNER JOIN dbo.tblStateCounties AS c 
    ON v.patientState = c.stateCode 
    AND v.patientCounty = c.countyCode
  WHERE c.stateCode = '21'
),
y AS (SELECT CountyName, c = COUNT(*) FROM x GROUP BY CountyName),
z AS (SELECT CountyName, c = COUNT(PatientID) FROM x 
  GROUP BY CountyName, patientState, PatientID HAVING COUNT(*)>1)
SELECT y.countyName, reAdmits = MAX(COALESCE(z.c, 0)), totalVisits = MAX(y.c)
FROM y LEFT OUTER JOIN z
ON y.CountyName = z.CountyName
GROUP BY y.CountyName;