MySQL and PHP: How to make it work without killing your server - Page 2

MySQL queries probably slow down your pageloads more than anything else. A big server-killer comes from queries inside loops--sometimes unavoidable but in most cases there are things that could be done to lighten the server load.

When you have built enough websites you will see that you use many things over and over again. At some point it just becomes simpler to chuck that into a class and store it in some sort of archive that way you can dip into whenever you lay out the structure of a new site. Being an OOP junkie, I have a simple class that first defines the array which creates my database connection.

File: dbConfig.php

  <?php

  Class dbConfig
  {
    public $config = array(
    'db_server'    => 'server_name',
    'db_name'      => 'database_name',
    'db_username'  => 'username',
    'db_password'  => 'password'
    );
  }

And then I keep a database class in my site library that references these configs and in turn supplies the site with a database connection as well as a few inbuilt functions that make sure my code is always perfect no matter what I do. The simplest version of my database class follows here:

File: db.php

  <?php

  Class db extends dbConfig
  {
    public $connection;

    public function __construct()
    {
      $this->connect();
    }

    public function connect()
    {
      $this->connection=mysql_connect($this->config['db_server'],$this->config['db_username'],$this->config['db_password']);
      if($this->connection):
        @mysql_select_db($this->config['db_name'],$this->connection);
      endif;
    }

    function updateTable($table, $field, $value, $id)
    {
      return mysql_query("update {$table} set {$field} = '{$value}' where id = {$id}", $this->connection);
    }

    function deleteFromTable($table, $id)
    {
      return mysql_query("delete from {$table} where id = {$id} limit 1", $this->connection);
    }

    function getArray($query)
    {
      if($result = @mysql_query($query, $this->connection))
      {
        while($tmp = @mysql_fetch_array($result))
          $dbarray[]= $tmp;

        if (isset($dbarray))
          return $dbarray;
        else return NULL;
      }
      return;
    }

    function query($query)
    {
      return mysql_query($query, $this->connection);
    }
  };

  $db = new db;

In essence, this gives me a very simple database framework that allows me to manage the simple queries I need to do on the site. Since I have started working with MVC Frameworks, however, I have found that this way is not really workable. But for procedural coding it still works well. Simply include both the dbConfig.php and db.php files in your includes file or make sure your autoloader knows where to find them and you are set.