小编use*_*394的帖子

我正在运行以下代码,但它返回一个错误: "undefined index: value"

$two_tier= mysql_query("
    SELECT Count(1)
    FROM(
        SELECT `login_id`
        FROM `data`
        WHERE Year(`start_at`) = Year(Date_sub(Now(), INTERVAL 1 month))
        AND Month(`start_at`) = Month(Date_sub(Now(), INTERVAL 1 month)) 
        AND end_at > Date_add(start_at, INTERVAL 5 minute) 
        GROUP  BY `login_id`
        HAVING Count(`login_id`) > 1
    ) AS Value
");

$two_cnt = mysql_fetch_assoc($two_tier);
echo $two_cnt['value'];

我想要获得"价值".请帮忙.