Question

I want to be able to make classes which extend the MySQLi class to perform all its SQL queries.

$mysql = new mysqli('localhost', 'root', 'password', 'database') or die('error connecting to the database');

I dont know how to do this without globalising the $mysql object to use in my other methods or classes.

class Blog {

public function comment() {
    global $mysql;

    //rest here
}

}

Any help would be appreciated.

Thanks.

Answer 1

My suggestion is to create a Singleton DataAccess class, instantiate that class in a global config file and call it in your Blog class like $query = DataAccess::query("SELECT * FROM blog WHERE id = ".$id).

Look into the Singleton pattern, it’s a pretty easy to understand designpattern. Perfect for this situation.

Your DataAccess class can have several methods like query, fetchAssoc, numRows, checkUniqueValue, transactionStart, transactionCommit, transactionRollback etc etc. Those function could also be setup as an Interface which gets implemented by the DataAccess class. That way you can easily extend your DataAccess class for multiple database management systems.

The above pretty much describes my DataAccess model.