多个PHP动态变量显示其他动态变量值

Question

I am generating dynamic variables like so:

    $testPMA = '';
    $result = mysql_query("SELECT * FROM site_pma") or die(mysql_error());  
      while($row = mysql_fetch_array($result)) {
        ${$testPMA.$row['id']} = $row['value'];
      } 
    $testLocation = '';
    $result = mysql_query("SELECT * FROM site_location") or die(mysql_error());  
      while($row = mysql_fetch_array($result)) {
        ${$testLocation.$row['id']} = $row['value'];
      } 

then I try displaying them like so:

    if(isset(${$testPMA.$row_bom_lines['pma']})) echo ${$testPMA.$row_bom_lines['pma']};

The first one returns correctly. The next column and any after always take their id number for the dynamic variable, but only generate PMA. They never update to show Location or any other one I have created. I even tried mysql_free_result($result); after each one. How do I get the dynamic variable to display each of their own vs displaying the same table information for each column, just with an updated id number?