Styling OOP - produced Tables in PHP

<?php
 
class db {			//handles database connections
 
private $hostname;
private $username;
private $password;
private $select_db;
private $connection;
 
public function __construct() {
 
$this -> hostname = "[hostname]";
$this -> username = "[username]";
$this -> password = "[password]";
$this -> select_db = "[database]";
 
}
 
 
public function open_connection() {
 
try {
 
$this -> connection = mysql_connect($this -> hostname, $this -> username, $this -> password);
$this -> select_db = mysql_select_db($this -> select_db);
 
}
 
catch (exception $e)
 
{return $e;}
 
}
 
 
public function close_connection() {
 
try { mysql_close ($this -> connection); }
 
catch(exception $e)
 
{return $e;}
 
}
 
} //end class
 
 
/*		*******		*******		*******		*******		*******		*******		*/
 
 
 
class query {
 
public $num_results;
public $result = array();
 
 
function __construct() {
 
$conn = new db;
$conn -> open_connection();
 
}
 
 
 
public function select($table, $rows = '*', $where = null, $order = null)  {	//runs select query using specified parameters
 
  
$sql = 'SELECT '.$rows.' FROM '.$table;  	//build up the query 
        
	if($where != null)  
	$sql .= ' WHERE '.$where;  				//...
            
	if($order != null)  
	$sql .= ' ORDER BY '.$order;  			//...
       
 
	if($query = mysql_query($sql)) {		//check query is OK, or return false
	  
	$this -> num_results = mysql_num_rows($query);  	//get number of rows
	
	for($i = 0; $i < $this -> num_results; $i++) {
	  
		$r = mysql_fetch_array($query);  
		$key = array_keys($r);   
		
			for($x = 0; $x < count($key); $x++) {     // Sanitizes keys so only alphavalues are allowed  
			  				
				if(!is_int($key[$x])) {			//if the array key isn't a number...
				  
					if($this -> num_results > 1)  		//...and there's more than one row
					$this -> result[$i][$key[$x]] = $r[$key[$x]];  	//set $result array to $result[incr. number][column name]
 
					else if($this -> num_results < 1)  //or there's no rows
					$this->result = null;				//set result to null
					
					else  								//or there's only 1 row
					$this->result[$key[$x]] = $r[$key[$x]]; 	//set $result array to $result[column name]
                  
				}  
			}
  
	}              
 
	return true;
	
	}  
    
    else {return false;}  
 
}	//end function
 
}	//end class
 
 
 
 
 
/*		*******		*******		*******		*******		*******		*******		*/
 
 
class table {
 
public $table;
 
 
public function __construct() {
 
;
 
}
 
 
public function add_header($header) {		//takes an array and converts to table header
 
$this -> table .= "<tr>\n";
 
foreach($header as $cell)
 
$this -> table .= "<th>$cell</th>\n";
 
$this -> table .= "</tr>\n";
 
}
 
 
public function add_rows($data) {
 
	if($data[0]) {				//checks if multidimensional array has been passed (i.e more than 1 row returned)
 
		foreach($data as $row) {		//loops through all arrays. $row remains an array because of multidimensional array input
		
			$this -> table .= "<tr>\n";		
 
			foreach ($row as $cell) {		//takes $row array and runs loop to extract actual data as $cell
 
				$this -> table .= "<td>$cell</td>\n";
 
				}
	
		$this -> table .= "</tr>\n";
	
		}
 
	} //end if
 
	else {		//this runs if the array passed was one-dimensional
 
	$this -> table .= "<tr>\n";
 
	foreach($data as $cell) {
	
		$this -> table .= "<td>$cell</td>\n";
	
		}
	
	$this -> table .= "</tr>\n";
 
	} //end else
 
} //end function
 
 
public function show_table() {		//takes the $table variable containing all the table cells, puts <table> tag either side, and returns it.
 
return "<table>\n" . $this -> table . "</table>\n" ;	
 
} //end function
 
} //end class
 
?>
 
 
EXAMPLE CODE - for generating a results table from a search form
 
<?php
 
if(isset($_POST['search'])) {
 
$search = $_POST['search'];
 
$cust_search = new query();     //new query object
$cust_search -> select('customer', 'customer_id, first_name, last_name, address_c_city, address_c_state', "first_name LIKE '%$search%' OR last_name LIKE '%$search%'");  //execute select statement with enclosed parameters
 
if($cust_search -> num_results == 0) echo "<div class='row w100'><p>No customers found.</p></div>";   //output if no customers found
 
$cust_table = new table();    //create new table object
$cust_table -> add_header( array("ID","First Name","Last/Co. Name","City","Region") ); // set header row
$cust_table -> add_rows($cust_search -> result);   //run add_rows function with the search result passed as an array
echo $cust_table -> show_table();  //output table