<?php

class Conn extends PDO {
    private $user='postgres';
    private $pass='202020';
    private $options=null;

    private static $instance;

    function __construct() {
        try {
            parent::__construct('pgsql:host=localhost;dbname=banco1', $this->user, $this->pass, $this->options);
        } catch (PDOException $ex) {
            print ($ex->getMessage());
        }
    }
    public static function getInstance() {
        if (!isset(self::$instance)) {
            self::$instance = new Conn();
        }
        return (self::$instance);
    }

    function __destruct() {
       self::$instance = null;
    }
}