資料庫備份工具

class DatabaseClone
{
    public $link;

    public function __construct($host, $username, $password)
    {
        $this->link = mysqli_connect($host, $username, $password);
        mysqli_query($this->link, 'SET NAMES utf8');
        mysqli_query($this->link, 'SET AUTOCOMMIT = 0');
        mysqli_query($this->link, 'SET UNIQUE_CHECKS = 0');
        mysqli_query($this->link, 'SET FOREIGN_KEY_CHECKS = 0');
    }

    public function fetch($query)
    {
        $results = [];
        $query = mysqli_query($this->link, $query);
        while ($row = mysqli_fetch_assoc($query)) {
            $results[] = $row;
        }

        return $results;
    }

    public function copy($copyTo)
    {
        set_time_limit(-1);
        ini_set('memory_limit', -1);
        $query = mysqli_query($this->link, $sql = 'show databases');
        while ($database = mysqli_fetch_assoc($query)) {
            $database = $database['Database'];
            if (in_array($database, ['mysql', 'information_schema', 'performance_schema'], true) === true) {
                continue;
            }

            $createDatabase = mysqli_fetch_assoc(mysqli_query($this->link, 'SHOW CREATE DATABASE `'.$database.'`'));
            mysqli_query($copyTo->link, $sql = 'DROP DATABASE IF EXISTS `'.$database.'`') or var_dump($sql);
            mysqli_query($copyTo->link, $sql = $createDatabase['Create Database']) or var_dump($sql);

            mysqli_select_db($this->link, $database);
            mysqli_select_db($copyTo->link, $database);

            $query2 = mysqli_query($this->link, $sql = 'show tables');
            while ($table = mysqli_fetch_assoc($query2)) {
                $table = current($table);
                $createTable = mysqli_fetch_assoc(mysqli_query($this->link, 'SHOW CREATE TABLE `'.$table.'`'));
                mysqli_query($copyTo->link, $sql = $createTable['Create Table']) or var_dump($sql);
                $counts = current(mysqli_fetch_assoc(mysqli_query($this->link, 'SELECT COUNT(*) as counts FROM `'.$table.'`')));
                $range = range(0, $counts - 1);
                $offset = 0;
                $limit = 200;
                $chunks = array_chunk($range, $limit);
                foreach ($chunks as $chunk) {
                    $query3 = mysqli_query($this->link, $sql = 'SELECT * FROM `'.$table.'` LIMIT '.$limit.' OFFSET '.$offset) or var_dump($database, $sql);
                    while ($row = mysqli_fetch_assoc($query3)) {
                        $keys = [];
                        $values = [];
                        foreach ($row as $key => $value) {
                            $keys[] = '`'.$key.'`';
                            $values[] = "'".addslashes($value)."'";
                        }
                        mysqli_query($copyTo->link, $sql = 'INSERT INTO `'.$table.'` ('.implode(',', $keys).') VALUES ('.implode(',', $values).')') or var_dump($database, $sql);
                    }
                    $offset += count($chunk);
                }
            }
        }
    }
}

$database = new DatabaseClone('localhost:3306', 'root', '');
$database->copy(new DatabaseClone('localhost:3308', 'root', ''));