PHP & MySQLi create table select insert update delete

At the start of working with MySQLi on PHP we must create connection:

$mysqli = new mysqli(DB_HOST,DB_USER,DB_PASSWORD,DB_NAME) or die('Not connected');
$mysqli->set_charset(DB_CHARSET);
if (mysqli_connect_errno()) {
    printf("Error connection this website: %s\n", mysqli_connect_error());
    exit();
}

Example how to create table with PHP on MySQL database.

$sql_create_tbl="CREATE TABLE IF NOT EXISTS `mytable` (
  `id` int(8) NOT NULL AUTO_INCREMENT,
  `post_id` bigint(20) UNSIGNED NOT NULL DEFAULT '0',
  `name` char(25) NOT NULL,
  `status` varchar(20) NOT NULL DEFAULT 'publish',
  `pretext` text,
  `content` longtext,
  `post_date` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
  `IP` varchar(255) NOT NULL,
  `date` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
  `uid` int(9) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;";
$mysqli->query($sql_create_tbl);

Example how to select row from table with PHP on MySQL database.

$var = 1;
if ($stmt = $mysqli->prepare("SELECT  title FROM `mytable` WHERE uid=?")) {
    $stmt->bind_param("s", $var);
    $stmt->execute();
    $stmt->bind_result($district);
    $stmt->fetch();
        // printf("%s in %s\n", $var, $district);
echo $district;
    $stmt->close();
}
$mysqli->close();

Or count rows in table

$result = $mysqli->query("SELECT count(*) as countees FROM `mytable`");
$row = $result->fetch_row();
echo '#: ', $row[0];

Example how to update row in table with PHP on MySQL database.

$mysqli->query("UPDATE  `mytable` SET uid= '1'  WHERE  id = '".$id."'; ");

Example how to insert values to table with PHP on MySQL database.

$mysqli->query("INSERT INTO  `mytable` (id, name, uid)  VALUES (1, 'example', 3) ; ");

Or use the statement with insert/update:

$mysqli->query("INSERT INTO   `mytable` (id, a, b)  VALUES (1, 2, 3)
ON DUPLICATE KEY  UPDATE a=a, b=b;");

Example how to delete row from table with PHP on MySQL database.

$stmt = $mysqli->prepare("DELETE FROM `mytable` WHERE id= ?");
$stmt->bind_param('i', $_POST['ID']);
$stmt->execute();
$stmt->close();

Example how to alter table with PHP on MySQL database for adding keys.

$mysqli->query("ALTER TABLE `mytable`
  ADD KEY `key_post_id` (`name`,`post_id`,`id`),
  ADD KEY `uid` (`uid`);");