Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= orwhen the subquery is used as an expression - sql

Question

I am having this error message. I have tried many other ways but can't resolve the issue.
I would be really grateful if someone could look at this :
;WITH progression
AS
(
SELECT
w.CustomerID,
CASE WHEN SUM(CASE WHEN w.workflowoutcomeid = 8 THEN 1 ELSE 0 END) > 0 THEN 'Yes' ELSE 'No' END AS [PG01],
CASE WHEN SUM(CASE WHEN w.workflowoutcomeid = 11 THEN 1 ELSE 0 END) > 0 THEN 'Yes' ELSE 'No' END AS [PG03],
CASE WHEN SUM(CASE WHEN w.workflowoutcomeid = 14 THEN 1 ELSE 0 END) > 0 THEN 'Yes' ELSE 'No' END AS [PG04],
CASE WHEN SUM(CASE WHEN w.workflowoutcomeid = 17 THEN 1 ELSE 0 END) > 0 THEN 'Yes' ELSE 'No' END AS [PG05],
CASE WHEN SUM(CASE WHEN w.workflowoutcomeid = 9 THEN 1 ELSE 0 END) > 0 THEN 'Yes' ELSE 'No' END AS [in_work_review]
FROM
ABC.dbo.tblWorkflow w
WHERE
w.Deleted IS NULL
AND
w.workflowqueueid = 4
AND
w.workflowoutcomeid IN (8, 11, 14, 17, 9)
GROUP BY
w.CustomerID
),
contact_data
AS
(
SELECT
CustomerID, [Email], [Mobile], [Home]
FROM
(
SELECT
CustomerID,
CASE
WHEN ContactTypeID = 1 THEN 'Home'
WHEN ContactTypeID = 2 THEN 'Mobile'
WHEN ContactTypeID = 5 THEN 'Email'
END AS ContactTypeDescription,
ContactValue
FROM ABC.dbo.tblCustomerContact
WHERE ContactTypeID IN (1,2,5)
) base
PIVOT
(
MAX(ContactValue) FOR ContactTypeDescription IN ([Home],[Mobile],[Email])
) pvt
),
appointment
AS
(
SELECT
n.[Key] AS CustomerID,
MAX(CASE WHEN n.AppointmentStatusID IN (2,4) THEN n.ActionDate ELSE NULL END) AS [Last_Completed_Attended_Appointment],
MAX(CASE WHEN n.AppointmentStatusID = 1 THEN n.ActionDate ELSE NULL END) AS [Next Pending Appointment]
FROM ABC.dbo.tblNote n
WHERE n.AppointmentTypeID = 6 AND n.AppointmentStatusID IN (1,2,4)
GROUP BY n.[Key]
)
SELECT
m.Firstname + ' ' + m.Lastname AS [Manager],
u.Firstname + ' ' + u.Lastname AS [Adviser],
c.CustomerID,
c.GivenName + ' ' + c.FamilyName AS [Customer Name],
g.Gender,
e.EthnicityName AS Ethnicity,
com.CompanyName,
NULL AS DeliverySite,
d.[Name] AS District,
css.ServiceStatus,
contact_data.Email,
uad.Line1 AS AddressLine1,
uad.Line2 AS AddressLine2,
uad.Line3 AS AddressLine3,
uad.Postcode,
uad.AlternativePostcode,
uad.Town,
ISNULL(contact_data.mobile, contact_data.home) AS Phone,
c.StartDate,
(SELECT MIN(wh.MGCReviewerModifiedDate) AS [ST01_Approved_Date]
FROM ABC.dbo.tblWorkflow w
INNER JOIN ABC.dbo.tblWorkflowHistory wh
ON w.WorkflowID = wh.WorkflowID
WHERE wh.WorkflowQueueID = 4 AND wh.MGCReviewerModifiedDate IS NOT NULL
AND wh.Deleted IS NULL AND w.WorkflowOutcomeID = 1 AND w.WorkflowQueueID = 4
AND w.Deleted IS NULL AND w.CustomerID = c.CustomerID
GROUP BY w.WorkflowID, w.CustomerID) AS ST01_Approved_Date,
qual.LearningAimTitle,
qual.LearningAimCompletionStatus,
qual.LearningAimOutcomeStatus,
mwp.WorkExperienceTitle ,
mwp.WorkExperienceStartDate,
mwp.WorkExperienceEndDate,
mwp.learningaimcompletionstatus as [Work_Ex_CompletionStatus],
mwp.learningaimoutcomestatus as [Work_Ex_OutcomeStatus],
p.PG01 AS [PG01_Start(Job Start Approved/Claimed ?)],
p.in_work_review AS [PG01_In_work_review(Job Outcome Approved/Claimed ?)],
p.PG03 AS [PG03 – Education Approved / Claimed?],
p.PG04 AS [PG04 – Apprenticeship Approved / Claimed?],
p.PG05 AS [PG05– Apprenticeship Approved / Claimed?],
a.Last_Completed_Attended_Appointment,
a.[Next Pending Appointment],
FLOOR(DATEDIFF(day, c.DateOfBirth, GETDATE()) / 365.25) as CustomerAge
FROM ABC.dbo.tblCustomer c
LEFT JOIN ABC.dbo.tblUser u ON c.OwnerID = u.UserID
LEFT JOIN ABC.dbo.tblUser m ON u.ManagerID = m.UserID
LEFT JOIN ABC.dbo.tlkpGender g ON c.GenderID = g.GenderID
LEFT JOIN ABC.dbo.tlkpEthnicity e ON c.EthnicityID = e.EthnicityID
LEFT JOIN ABC.dbo.tblCompany com ON c.CompanyId = com.[CompanyID]
LEFT JOIN ABC.dbo.tblCustomerAddress cad ON c.CustomerID = cad.CustomerID AND cad.EffectiveTo IS NULL
LEFT JOIN ABC.dbo.tblUKAddress uad ON uad.UKaddressID = cad.UKaddressID
LEFT JOIN PostcodeESyNCS.dbo.tblPostcode po ON uad.Postcode = po.Postcode
LEFT JOIN PostcodeESyNCS.dbo.tlkpDistrict d ON po.DistrictId = d.DistrictId
LEFT JOIN ABC.dbo.tlkpCustomerServiceStatus css ON c.CustomerServiceStatusID = css.CustomerServiceStatusID
LEFT JOIN progression p ON c.CustomerID = p.CustomerID
LEFT JOIN contact_data ON c.CustomerID = contact_data.CustomerID
OUTER APPLY
(
SELECT TOP 1
l.learningaimid,
aim.LearningAimTitle,
aim.isfullqualification,
st.LearningAimCompletionStatus,
aos.LearningAimOutcomeStatus
FROM ABC.dbo.tbllearning l
LEFT JOIN ABC.dbo.tlkplearningaim aim on aim.learningaimid = l.learningaimid
LEFT JOIN ABC.dbo.tlkplearningaimcompletionstatus st on st.learningaimcompletionstatusid = l.learningaimcompletionstatusid
LEFT JOIN ABC.dbo.tlkpLearningAimOutcomeStatus aos on aos.learningaimoutcomestatusid = l.learningaimoutcomestatusid
WHERE aim.learningaimtypeid = 1 AND l.customerid = c.customerid
ORDER BY l.StartDate DESC
) qual
OUTER APPLY
(
SELECT TOP 1
l.learningaimid,
REPLACE(aim.LearningAimTitle,',',' ') as WorkExperienceTitle,
aim.isfullqualification,
st.LearningAimCompletionStatus,
outcome.LearningAimOutcomeStatus,
l.StartDate as WorkExperienceStartDate,
l.ActualEndDate as WorkExperienceEndDate
FROM ABC.dbo.tbllearning l
LEFT JOIN ABC.dbo.tlkplearningaim aim ON aim.learningaimid=l.learningaimid
LEFT JOIN ABC.dbo.tlkplearningaimcompletionstatus st ON st.learningaimcompletionstatusid=l.learningaimcompletionstatusid
LEFT JOIN ABC.dbo.tlkpLearningAimOutcomeStatus outcome ON outcome.learningaimoutcomestatusid= l.learningaimoutcomestatusid
WHERE aim.LearningAimID IN (SELECT la.LearningAimID
FROM ABC.dbo.tlkpLearningAim la
WHERE la.LearningAimTypeID = 2
and la.LearningAimTitle like '%Work%')
AND l.customerid = c.customerid
ORDER BY StartDate DESC
) AS mwp
LEFT JOIN appointment a ON c.CustomerID = a.CustomerID
WHERE
c.Deleted IS NULL
I am getting the following error:
Msg 512, Level 16, State 1, Line 2
Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.
Warning: Null value is eliminated by an aggregate or other SET operation.

Answer 1

The only place where I see that this could be happening is the definition of ST01_Approved_Date:
(SELECT MIN(wh.MGCReviewerModifiedDate) AS [ST01_Approved_Date]
FROM ABC.dbo.tblWorkflow w JOIN
ABC.dbo.tblWorkflowHistory wh
ON w.WorkflowID = wh.WorkflowID
WHERE wh.WorkflowQueueID = 4 AND wh.MGCReviewerModifiedDate IS NOT NULL AND
wh.Deleted IS NULL AND w.WorkflowOutcomeID = 1 AND w.WorkflowQueueID = 4 AND
w.Deleted IS NULL AND w.CustomerID = c.CustomerID
GROUP BY w.WorkflowID, w.CustomerID
) AS ST01_Approved_Date,
A correlated subquery should not contain GROUP By for exactly this reason. I don't know what the logic would be, but there should probably be a condition on w.WorkFlowId to the outer query, something like:
(SELECT MIN(wh.MGCReviewerModifiedDate) AS [ST01_Approved_Date]
FROM ABC.dbo.tblWorkflow w JOIN
ABC.dbo.tblWorkflowHistory wh
ON w.WorkflowID = wh.WorkflowID
WHERE wh.WorkflowQueueID = 4 AND wh.MGCReviewerModifiedDate IS NOT NULL AND
wh.Deleted IS NULL AND w.WorkflowOutcomeID = 1 AND w.WorkflowQueueID = 4 AND
w.Deleted IS NULL AND w.CustomerID = c.CustomerID AND
w.workflowID = <outer query reference>.WorkflowId
) AS ST01_Approved_Date,