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Access alias in CASE statement

I am trying to create a column called DateStartedStatus that utilizes a previously aliased column to compute its value. It should use CurrentStatus to output a value and an error is showing that says “Invalid column name ‘CurrentStatus'”. How can I access that alias in the below case statement?

SELECT p.[ID]
  ,p.[Name] as 'ProcurementName'
  ,p.[FundingDocumentNumber] as 'FundingDocumentNumber'
  ,p.[Status]
  ,p.[Comments] as 'Comments'
  ,p.[isSAVE]
  ,p.[InWorkDate]
  ,p.[RoutedDate]
  ,p.[FundsCertifiedDate]
  ,p.[AwardedDate]
  ,p.[TransactionType]
  ,p.[FNMSStatus]
  ,p.[Closed]
  ,p.[Archived]
  ,p.[Cancelled]
  ,(CASE
    WHEN p.[Status] = 'In Work' THEN 'Pending'
    ELSE p.[Status]
   END) as CurrentStatus
  ,(CASE
   WHEN CurrentStatus = 'Awarded' THEN p.AwardedDate <-- fails here CurrentStatus not a column
   END) as DateStartedStatus
  ,(SELECT SUM(TotalCost) 
  FROM ProcurementsRequestLineItems subprlis
  LEFT JOIN RequestLineItems subrli ON subprlis.RequestLineItemID = subrli.ID
  WHERE ProcurementID = p.ID) as TotalCost
FROM Procurements p
WHERE p.Closed = 0 AND p.Archived = 0;

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Answer

Using subqueries like this

select ... CASE WHEN CurrentStatus ....
from
( --calculate Current_status here
select ....
    CASE
    WHEN p.[Status] = 'In Work' THEN 'Pending'
    ELSE p.[Status]
   END) as CurrentStatus 
   ...   
) s

Do not worry, subquery will not add computational complexity, optimizer will remove it if possible.

Another way is nested CASE expressions (query is not readable):

case when case ... some logic here ... end = 'Awarded'
     then ...
end
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