How can I use the group by Clause in a subquery

Question

I just need to select one more field in my query that is the date... but it's a subquery and i'm using a count field... and because of it i need to use the GROUP BY Clause... But i can't group by my subquery and the query is returning errors...

SELECT
X.NROF,
Z.NMGUERFORN,
C.CDCOMPRADO,
C.CDCOORDENA,
E.CDFUP,
count(*)  AS ocorrencias
--(select TOP 1 DTPROGENTR from CMPENL0 C (NOLOCK) where X.NRPEDICOMP = C.NRPEDICOMP AND X.NRITEMPECO = C.NRITEMPECO) AS DTPROGENTR
FROM  CMPCIL0 X (NOLOCK)
inner join CMPCCL0 Y (NOLOCK) on X.NRPEDICOMP  = Y.NRPEDICOMP
inner join CMFRNL0 Z (NOLOCK) on Y.CDFORNECED1 = Z.CDFORNECED1
inner join CMSCPL0 M (NOLOCK) on X.NRSOLICOMP  = M.NRSOLICOMP    AND X.NRITEMSC    = M.NRITEMSC
inner join CMPENL0 N (NOLOCK) on X.NRPEDICOMP  = N.NRPEDICOMP    AND X.NRITEMPECO  = N.NRITEMPECO
inner join CMMATL0 A (NOLOCK) on X.CDMATERIAL  = A.CDMATERIAL
inner join cmcomL0 c (NOLOCK) on c.cdcomprado = y.cdcomprado
LEFT  JOIN AMCSPL0 D (NOLOCK) ON D.SCPE_NRSOLICOMP = X.NRSOLICOMP AND D.SCPE_NRITEMSC=X.NRITEMSC
LEFT  JOIN CMFUPL0 E (NOLOCK) ON E.CDFORNECED1 = Z.CDFORNECED1
LEFT  JOIN CMPFIL0 H ON Z.CDFORNECED1 = H.CDFORNECED1 AND X.NRIDENTIFI = H.NRIDENTIFI and H.DTVALIDADE > Y.DTEFETPECO
LEFT JOIN CMPENL0 F ON (X.NRPEDICOMP = F.NRPEDICOMP AND X.NRITEMPECO = F.NRITEMPECO)
WHERE X.CDSTATUS = 'P' and X.NROF <> 0
group by X.NROF,Z.NMGUERFORN,C.CDCOMPRADO,C.CDCOORDENA,E.CDFUP--,DTPROGENTR
order by 6 desc

The commented parts are the code im trying to include to select the field, but it is giving me errors..

Answer 1

The problem is that you use aliases in your where clause of select sub-query. Aliases cannot be referenced on the same level in the query. You should use full qualified names and the sub-query should look something like that:

(select TOP 1 DTPROGENTR from CMPENL0 C (NOLOCK) where X.NRPEDICOMP = CMPENL0.NRPEDICOMP AND X.NRITEMPECO = CMPENL0.NRITEMPECO) AS DTPROGENTR

Answer 2

If your sql-server supports common table expressions you can try that:

;WITH cte AS
(
    SELECT ROW_NUMBER() OVER(PARTITION BY NRPEDICOMP, NRITEMPECO ORDER BY NRPEDICOMP) row_num
    ,DTPROGENTR
    ,NRPEDICOMP
    ,NRITEMPECO 
    FROM CMPENL0 (NOLOCK)
)
SELECT
X.NROF,
Z.NMGUERFORN,
C.CDCOMPRADO,
C.CDCOORDENA,
E.CDFUP,
count(*)  AS ocorrencias
cte.DTPROGENTR
FROM  CMPCIL0 X (NOLOCK)
inner join CMPCCL0 Y (NOLOCK) on X.NRPEDICOMP  = Y.NRPEDICOMP
inner join CMFRNL0 Z (NOLOCK) on Y.CDFORNECED1 = Z.CDFORNECED1
inner join CMSCPL0 M (NOLOCK) on X.NRSOLICOMP  = M.NRSOLICOMP    AND X.NRITEMSC    = M.NRITEMSC
inner join CMPENL0 N (NOLOCK) on X.NRPEDICOMP  = N.NRPEDICOMP    AND X.NRITEMPECO  = N.NRITEMPECO
inner join CMMATL0 A (NOLOCK) on X.CDMATERIAL  = A.CDMATERIAL
inner join cmcomL0 c (NOLOCK) on c.cdcomprado = y.cdcomprado
LEFT  JOIN AMCSPL0 D (NOLOCK) ON D.SCPE_NRSOLICOMP = X.NRSOLICOMP AND D.SCPE_NRITEMSC=X.NRITEMSC
LEFT  JOIN CMFUPL0 E (NOLOCK) ON E.CDFORNECED1 = Z.CDFORNECED1
LEFT  JOIN CMPFIL0 H ON Z.CDFORNECED1 = H.CDFORNECED1 AND X.NRIDENTIFI = H.NRIDENTIFI and H.DTVALIDADE > Y.DTEFETPECO
LEFT JOIN CMPENL0 F ON X.NRPEDICOMP = F.NRPEDICOMP AND X.NRITEMPECO = F.NRITEMPECO
LEFT JOIN cte ON X.NRPEDICOMP = cte.NRPEDICOMP AND X.NRITEMPECO = cte.NRITEMPECO AND cte.row_num = 1
WHERE X.CDSTATUS = 'P' and X.NROF <> 0
group by X.NROF,Z.NMGUERFORN,C.CDCOMPRADO,C.CDCOORDENA,E.CDFUP, cte.DTPROGENTR
order by 6 desc