Case When with Count inside an ON clause of a JOIN - sql-server

Question

Inside the JOIN (BB_VENDASDOCUMENTOS VD), I need to choose if VD.ENTRADASAIDA will be 'S' or 'E', what I actually need is, if there is at least one BB_VENDASDOCUMENTOS where ENTRADASAIDA = 'S', use 'S', else 'N'
I've tried to do a CASE WHEN counting the numer of VD.ENTRADASAIDA = 'S', if there is more then 0, It will use 'S', else 'N', but I'm getting an error that and aggregate cannot appear in an ON clause...
SELECT
CASE WHEN CENTROCUSTO.DESCRICAO IS NOT NULL THEN CENTROCUSTO.DESCRICAO + '|' ELSE '' END AS [text()]
FROM BB_PNRACCOUNTINGS ACC1
JOIN BB_VENDASDOCUMENTOS VD
ON ( VD.ACCOUNTING = ACC1.HANDLE
AND VD.ENTRADASAIDA = CASE WHEN count(case when VD.ENTRADASAIDA = 'S' THEN 1 ELSE NULL END ) > 0 THEN 'S' ELSE 'E' END
AND VD.PESSOA = ACC1.BB_CLIENTE
AND ( ( VD.CANCELADO = 'N' ) OR (VD.CANCELADO IS NULL) ) )
LEFT JOIN BB_CLIENTECC CENTROCUSTO
ON (CENTROCUSTO.Handle = VD.CENTRODECUSTO)
WHERE CENTROCUSTO.DESCRICAO IS NOT NULL

Answer 1

You will need to scan the table twice. Once to mark each group with a S or E and then to gather only the records that match the condition. I would do this by joining on a subquery and then join again on the condition. I am not sure the syntax below is 100% correct, however, the basic concept is there.
;WITH BB_VENDASDOCUMENTOSCalc AS
(
SELECT ACCOUNTING,PESSOA,
ENTRADASAIDACalc = count(case when ENTRADASAIDA = 'S' THEN 1 ELSE NULL END ) > 0 THEN 'S' ELSE 'E' END
FROM
BB_VENDASDOCUMENTOS
WHERE
(CANCELADO='N' OR CANCELADO IS NULL)
GROUP BY
ACCOUNTING,
PESSOA
)
SELECT
CASE WHEN CENTROCUSTO.DESCRICAO IS NOT NULL THEN CENTROCUSTO.DESCRICAO + '|' ELSE '' END AS [text()]
FROM BB_PNRACCOUNTINGS ACC1
JOIN BB_VENDASDOCUMENTOSCalc VD1 ON VD1.ACCOUNTING = ACC1.HANDLE AND VD1.PESSOA = ACC1.BB_CLIENTE
JOIN BB_VENDASDOCUMENTO VD ON VD.ACCOUNTING = ACC1.HANDLE AND VD.PESSOA = ACC1.BB_CLIENTE AND VD.ENTRADASAIDA = VD1.ENTRADASAIDACalc
LEFT JOIN BB_CLIENTECC CENTROCUSTO
ON (CENTROCUSTO.Handle = VD.CENTRODECUSTO)
WHERE CENTROCUSTO.DESCRICAO IS NOT NULL