CODE:

 $value) {
            $sql .= sprintf('`%s` = ?, ', $column);
        }
        $sql = preg_replace('/,\s$/','', $sql);
    }
    if (!empty($onDuplicateKeyUpdate)) {
        $sql .= 'ON DUPLICATE KEY UPDATE ';
        foreach ($onDuplicateKeyUpdate as $key => $value) {
            $sql .= sprintf('`%s` = %s, ', $key);
        }
        $sql = preg_replace('/,\s$/','', $sql);
    }
    return $sql;
}

CODE:

I 'テスト',
    'email' => 'naolin_17_1986@yahoo.co.jp',
    'url' => 'http://www.yahoo.co.jp',
    'password' => '1234',
    'main' => '今日もがんばろう',
    'time' => 'CURRENT_TIMESTAMP()',
    'ip' => $_SERVER['REMOTE_ADDR']
];
$sql = insertSql('users', $parameter);

echo  $sql;

CODE:

INSERT INTO users SET `name` = ?, `email` = ?, `url` = ?, `password` = ?, `main` = ?, `time` = ?, `ip` = ?