optimize connections to mysql - php

Question

i have a php site
in index file include connect to db function :
function connect(){
mysql_connect("localhost", "user", "pass") or die(mysql_error());
mysql_select_db("database");
}
and i use this function in everywhere i need connection
for example:
<?php
connect();
$lastnews_sql = mysql_query("SELECT text,time FROM small WHERE active='0' ORDER BY time DESC LIMIT 10");
if(mysql_num_rows($lastnews_sql)) {
while($Result123 = mysql_fetch_object($lastnews_sql)) {
?>
and use this selection:
text; ?>
in end of using :
<?php
}
}
mysql_close();
?>
there are more than 10 connect(); and mysql_close(); in index file
so there are too many connection error in index file
how can i optimize this metod ?

Answer 1

A singleton pattern seems to suit this down to the ground.
class Database
{
private static $instance;
public function getInstance()
{
if(self::$instance == null)
{
// Create a connection to the database.
// NOTE: Use PDO or mysqli. mysql is deprecated.
}
return self::$instance;
}
}
Use
In your classes, instead of calling connect, assuming you're using a PDO object, you could do something like:
$db = Database::getInstance();
$statement = $db->prepare("SELECT * FROM tblName WHERE val = :val");
$statement->bindParam(":val", $value);
$statement->execute();
$result = $statement->fetchAll();
Why this pattern ?
A Singleton pattern has the advantage of only having one instance of itself exist at one time. That means that you will only ever create one connection to the database.
Setting this up
Okay, so the first thing you want to do is to make a new file, let's call it Database.php. Inside Database.php, you want to pretty much write the code that I've written, only do NOT use mysql_*. Have a look at the PDO tutorial that I have provided, on how to connect to a database using a PDO object, and then you put that connection code inside the if statement, so it might look something like:
if(self::$instance == null)
{
self::$instance = new PDO('mssql:host=sqlserver;dbname=database', 'username', 'password');
}
Then, to use it in another class, put a require statement at the top. Something like:
require_once('Database.php');
Finally, look at the code I put in the use section, above. That is how you use it in your class.
Useful links
PDO Tutorial : http://php.net/manual/en/book.pdo.php
Singleton Pattern : http://www.oodesign.com/singleton-pattern.html