SQL & PL/SQL

Dear All

I Have The Following Tables


Table A As Val As Column Contains - 1,2,3,5,6
Table B As Val As Column Contains- 2,3,4

When I Am Using Query

Using Intersect


Select Val From A Where Val In (1,2,3) - Q1
Intersect
Select Val From B Where Val In (2,3) -Q2

Now I Get Result As 2,3 Only When Two Q1,Q2 Are Executed.

Then I Am Using

Select Val From A Where Val In (5,6) - Q1
Intersect
Select Val From B Where Val In (2,3) -Q2

Now I Got No Rows Return

But I Want The Query Q2 Result Separatly When Q1 Is Also Not Fired. If Q1,Q2 Is Fires Common Values
Only To Be Return....


If Any Idea Bout Query ??????????


Thanks

K.Prabakaran