In a given select I can reference two tables by foreign keys.
Ex: IdA / IdB
IdA = IdB
Table A has a column named C
Table B has three columns called D, E, F
Both tables have similar contents for returns in SELECT
Ex:
Select ... from table A a, table B b Where a.IdA = b.IdB and a.C = b.D and a.C = b.E and a.C = a.F...
When I put the condition And returns null When I put OR returns incomplete data, PQ?