Hi,
I run this query

SELECT A.COD, A.FLAG, B.AREA, B.NUM_ID
FROM TAB A, TAB1 B
WHERE A.ID=B.ID
AND ((FLAG=1 AND COD <> 'M') OR (FLAG=2 AND COD = 'N'))

With this query I get:

no row select ( there are rows with flag=1 and cod<>'M')

but if I run this query:

SELECT A.COD, A.FLAG, B.AREA, B.NUM_ID
FROM TAB A, TAB1 B
WHERE A.ID=B.ID
AND (FLAG=1 AND OR (FLAG=2 AND COD = 'N'))

I get rows


What I wrong??

Thanks
Raf