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How to use conditional column values ​​in the same select clause?

I have something like

( COMPLEX_EXPRESSION_Nstands for long subquery)

select
  ID_Operation,
  FirstCheck = CASE WHEN (COMPLEX_EXPRESSION_1)= 0 then 0 else 1 end,
  SecondCheck = CASE WHEN (COMPLEX_EXPRESSION_2)= 0 then 0 else 1 end,
  ThirdCheck = CASE WHEN (COMPLEX_EXPRESSION_3)= 0 then 0 else 1 end,
  AllChecksOk = Case WHEN 
               (FirstCheck + SecondCheck + Third CHeck = 3) 
               Then 'OK' Else 'No' End
from 
  AllOperationsTable

Can I use FirstCheck, SecondCheck, ThirdCheck, as in the AllChecksOk line?

I'm not interested in performance, it's that it is launched manually once a day on a very small number of records, I just want to avoid creating views, tables or temporary tables and save everything in one select statement.

As an altenrative, I can do this, but makes the request less readable (since I need to write twice each complex expression):

select
  ID_Operation,
  FirstCheck = CASE WHEN (COMPLEX_EXPRESSION_1)= 0 then 0 else 1 end,
  SecondCheck = CASE WHEN (COMPLEX_EXPRESSION_2)= 0 then 0 else 1 end,
  ThirdCheck = CASE WHEN (COMPLEX_EXPRESSION_3)= 0 then 0 else 1 end,
  AllChecksOk = Case WHEN 
               (COMPLEX_EXPRESSION_1+ COMPLEX_EXPRESSION_2+ 
               COMPLEX_EXPRESSION_3CHeck = 3) Then 'OK' Else 'No' End
from 
  AllOperationsTable
+5
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2 answers

select, CTE, .

;WITH CTE AS
(
select
  ID_Operation,
  FirstCheck = CASE WHEN (COMPLEX_EXPRESSION_1)= 0 then 0 else 1 end,
  SecondCheck = CASE WHEN (COMPLEX_EXPRESSION_2)= 0 then 0 else 1 end,
  ThirdCheck = CASE WHEN (COMPLEX_EXPRESSION_3)= 0 then 0 else 1 end
from 
  AllOperationsTable
)
SELECT *,
       AllChecksOk = Case WHEN 
               (COMPLEX_EXPRESSION_1+ COMPLEX_EXPRESSION_2+ 
               COMPLEX_EXPRESSION_3CHeck = 3) Then 'OK' Else 'No' End
FROM CTE

CROSS APPLY , select .

+4

SELECT
  T.ID_Operation,
  FirstCheck   = CASE WHEN T.Expr1 = 0 THEN 0 ELSE 1 END,
  SecondCheck  = CASE WHEN T.Expr2 = 0 THEN 0 ELSE 1 END,
  ThirdCheck   = CASE WHEN T.Expr3 = 0 THEN 0 ELSE 1 END,
  AllChecksOk  = CASE WHEN T.Expr1 + T.Expr2 + T.Expr3 = 3 THEN 'OK' ELSE 'No' END
FROM
(
  SELECT
    ID_Operation,
    Expr1 = (COMPLEX_EXPRESSION_1),
    Expr2 = (COMPLEX_EXPRESSION_2),
    Expr3 = (COMPLEX_EXPRESSION_3)
  FROM 
    AllOperationsTable
) T
+3

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