search data in table with user inputs in php with mysql

connection.inc.php :

<?php
$host='localhost';
$user_name='root';
$password='';
@$con = mysql_connect("$host","$user_name","$password");
if ($con)
 {}
else
  {
  die('Could not connect ');
  }
?>
=======================================================================

select_form.php :


<center><form action="select_table.php" method="POST">
<table border=0><tr><td>database name</td><td><input type="text" name="db_name" value="test"></td>
<td>table name</td><td><input type="text" name="table_name" value="test"></td></tr>
<tr><td>column1 name</td><td><input type="text" name="col1" value="sno"></td>
<td>column2 name</td><td><input type="text" name="col2" value="name"></td></tr>
<tr><td colspan=4 align="center"><input type="submit" value="submit"> </td></tr></table>
</form>

===================================================================

select_table.php :


<?php

require 'connection.inc.php';

if (@mysql_select_db($_POST['db_name']))
{
     if(isset($_POST['db_name'])&& isset($_POST['table_name'])&& isset($_POST['col1'])&& isset($_POST['col2']))
        {
         if(!empty($_POST['db_name'])&& !empty($_POST['table_name'])&& !empty($_POST['col1'])&& !empty($_POST['col2']))
             {
               $db=$_POST['db_name'];
               $tn=$_POST['table_name'];
               $snum=$_POST['col1'];
               $name=$_POST['col2'];
               $result=mysql_query("select * from $tn ",$con);

                          if(mysql_query("select * from $tn ",$con))
                          {
                              if(@mysql_num_rows($result))
                                {
                               echo ("<br><center><table><tr><th><b>$snum</td><th><b>$name</td></tr>");
                               if(mysql_query("select $snum from $tn") && mysql_query("select $name from $tn"))
                               {
                               while($data = mysql_fetch_array($result))
                                     {
                                      echo "<tr><td>".@$data[$snum] . "</td><td>" .@$data[$name]."</td></tr>";
                                     }
                                    }else {
                                            echo '<b>please verify column name(s)</b>';
                                          }

                         }   else echo '<center><b>empty table';
                  }  else echo ('<center><br><br><b>no table with that name<br><br>');
              }
           else echo '<center>please varify is all data entered ?';
  } else echo '<center>one of the input ont set';
}else echo '<center><br>wrong database selected<br>';

mysql_close($con);
?>

=======================================================================

run " select_form.php "

output :

fill every text box and click on submit button