$query = "select * from 테이블 where index = ? and datestring = ?";

$stmt = $connect_db->prepare($query);

$ix = 30;

$date = '2023-10-10';

$stmt->bind_param('is', $ix, $date);

$stmt->execute();

$meta = $stmt->result_metadata();

while ($field = $meta->fetch_field()) {

    $params[] = &$row[$field->name];

}

call_user_func_array(array($stmt, 'bind_result'), $params);

while ($stmt->fetch()) {

    foreach ($row as $key => $val) {

        $c[$key] = $val;

    }

    $arr_memo[] = $c;

}

$stmt->close();