wildcard and mysql query - select all that matches 4* to 47* etc

I'm fairly new to PHP and I have a question.

I am trying to select all that matches the range [some number] to [some number] and allow the range to have wildcards inside a function. Variables are passed in (user input)

    $Query = "SELECT Num FROM table WHERE ";    
   
    // for wild cards
    $WildLow = substr_count($LOW, "*");
    $WildHigh = substr_count($HIGH, "*");
    $TempLow = str_replace("*", "", $LOW);
    $TempHigh = str_replace("*", "9999999999", $HIGH);

    // query with wildcards
    if ( ($WildLow > 0) || ($WildHigh > 0) ) {
      $Query .= " Num >= '$TempLow' ";
      $Query .= " AND ";
      $Query .= " Num <= 'TempHigh' ";
      GetRangeArray ($List, $Index, $Query);
      return;
    }

  However I keep getting invalid as its result whenever i pass in "*" as the range input.

  Any suggestions? Thanks.

ALso, what does this regular expression mean?       $Result = ereg("^[0-9\*]{1,". "10" . "}$", $Num);