같은 결과가 나올 줄 알았는데.. 결과가 다르게 나와서 놀랐어요~
왜 틀린지 혹시 아시나요?

SELECT * 
FROM FPDATAFUNCTIONWK
WHERE 
FPDATAFUNCTIONWK.KEMMEICD = '0606' AND 
FPDATAFUNCTIONWK.RIREKICD = '0002' AND 
FPDATAFUNCTIONWK.FPPATANITEMCD = '01' AND 
FPDATAFUNCTIONWK.FILETYPECD = '0001' AND 
FPDATAFUNCTIONWK.FILESEQ IN ( '2') AND 
FPDATAFUNCTIONWK.UPDID = '0606' AND 
FPDATAFUNCTIONWK.EDITFLG = '1'
AND EXISTS (
SELECT 1
FROM FPDATAFUNCTIONWK BEFOREDATA
WHERE 
BEFOREDATA.KEMMEICD = FPDATAFUNCTIONWK.KEMMEICD AND 
BEFOREDATA.RIREKICD = FPDATAFUNCTIONWK.RIREKICD AND 
BEFOREDATA.FPPATANITEMCD = FPDATAFUNCTIONWK.FPPATANITEMCD AND 
BEFOREDATA.FILETYPECD = FPDATAFUNCTIONWK.FILETYPECD AND 
BEFOREDATA.FILESEQ = FPDATAFUNCTIONWK.FILESEQ 
AND BEFOREDATA.EDITFLG = '0' ) ;
-> 아무것도 안나옴

SELECT * 
FROM FPDATAFUNCTIONWK
WHERE 
KEMMEICD = '0606' AND 
RIREKICD = '0002' AND 
FPPATANITEMCD = '01' AND 
FILETYPECD = '0001' AND 
FILESEQ IN ( '2') AND UPDID = '0606' AND 
EDITFLG = '1'
AND EXISTS (
SELECT 1
FROM FPDATAFUNCTIONWK BEFOREDATA
WHERE 
BEFOREDATA.KEMMEICD = KEMMEICD AND 
BEFOREDATA.RIREKICD = RIREKICD AND 
BEFOREDATA.FPPATANITEMCD = FPPATANITEMCD AND 
BEFOREDATA.FILETYPECD = FILETYPECD AND 
BEFOREDATA.FILESEQ = FILESEQ AND 
BEFOREDATA.EDITFLG = '0' ) ;
-> 한줄 나옴