check if any records match
if match ---rec match/not match
when used full outer join both tables
no name ph
1 X 0
2 Y 1
3 Z 2
4 A 3
no name ph
1 X 0
2 c 6
3 m 9
4 A 5
no name ph result
1 X 0 null--------------------------why im getting nul when there are records?
2 c 6 rec found
3 m 9 rec found
4 A 5 null------------------------why im getting nul when there are records?
5 Y 1 rec found