php-database-singleton-method

php-database-singleton-method

Class DbConn {

    private static $instance;
    private $dbConn;
        private $mysqli;


    private function __construct() {
       $this->mysqli = new mysqli("localhost", "root", "", "fetch_category");
        if ($this->mysqli->connect_error) {
            die($this->mysqli->connect_error);
        }
    
    }

    /**
     *
     * @return DbConn
     */
    private static function getInstance(){
        if (self::$instance == null){
            $className = __CLASS__;
            self::$instance = new $className;
             //self::$instance = new static();

        }

        return self::$instance;
    }

https://stackoverflow.com/questions/21832809/php-singleton-database-connection-pattern

https://hotexamples.com/examples/-/DataBase/singleton/php-database-singleton-method-examples.html
https://www.linkedin.com/pulse/singleton-php-ranush-malsika-loptc/?trk=public_post_main-feed-card_feed-article-content
https://devpress.csdn.net/mysqldb/62fc6d967e6682346618fb61.html
https://forums.phpfreaks.com/topic/293664-mysqli-singleton-class/
<?php
// $servername = "localhost";
// $username = "root";
// $password = "";
// $dbname = "fetch_category";
// $conn = mysqli_connect($servername, $username, $password, $dbname) or die("Connection failed");

class Database {
    public static $instance;
    private $mysqli,
            $query,
            $results,
            $count ;
          public  $last_inserted_id = 0;

 
    public static function getInstance() {
        if (!self::$instance) {
            self::$instance = new Database();
        }
        return self::$instance;
    }
        
    public function __construct() {
        $this->mysqli = new mysqli("localhost", "root", "", "fetch_category");
        if ($this->mysqli->connect_error) {
            die($this->mysqli->connect_error);
        }
    }

    public function query($sql) {
        if ($this->query = $this->mysqli->query($sql)) {

            if ($this->query->num_rows > 0) {

            while ($row = $this->query->fetch_assoc()) {
                $this->results[] = $row;
            }
        }
            $this->count = $this->query->num_rows;
        }
        return $this;
    }
    
    public function results() {
        return $this->results;
    }

    public function count() {
        return $this->count;
    }



    public function insertData($sql) {
        if ($this->query = $this->mysqli->query($sql)) {
            $this->last_inserted_id = $this->mysqli->insert_id;
        }
        return $this;
    }
 
 
}


$r = Database::getInstance()->query('SELECT * FROM employees');
foreach ($r->results() as $row) {
   echo $row['first_name']. $row['id']. '</br>';
}
echo $r->count();

echo '</br>';


$DB = Database::getInstance()->insertData("INSERT INTO `employees`(`id`, `first_name`, `last_name`, `email`, `phone`, `post`, `avatar`, `created_at`, `Updated_at`) 
VALUES ('aaaa','aa','[value-3]','[value-4]','[value-5]','[value-6]','[value-7]','[value-8]','[value-9]');
");

echo $DB->last_inserted_id;

https://stackoverflow.com/questions/4165195/mysql-query-to-get-column-names
https://www.codexworld.com/php-crud-operations-jquery-ajax-mysql/