GIS location filtering

[#1]

I have tables which have location. 

Example

     US counties

     World countries.

I have anther table which have values and location also

   example

       NY .    (inside US).

now I want to make the relation between tables spatially based on location       

      EX. If I choose  US counties it will filter only places inside US based on location attribute

Is this possible.

[SunilChauhan]

make the column name same in all tables

[#3]

This will not solve the issue,

As i am not looking for 2 fields with same values but one field with value that is totaly inside anther field value. This the GIS

Example

    if my city boundary is rectangle with coordinate x,y,x1,y1  (0,0,10,10) then

     if I have field with one point value x,y (5,5) then this field belong to the first one

so its kind of spatial join.

Thanx