计数的活动记录数两个日期

Question

我试图做一个查询中检索给定时间主动呼叫的数量之间，

我有一个表与所有与AnsweredTime和ReleaseTime的通话记录通话我需要在一天中检索每秒激活的通话数。

所以我做了以下内容：

SELECT dt, 
(SELECT COUNT(Id) FROM Calls WHERE 
    AnsweredTimestamp <= dt AND 
    ReleasedTimestamp >= dt) 
FROM CALView 
WHERE dt >='2011-10-05' 
and dt <'2011-10-06' 

CalView是包含两个日期

之间每隔一表的查询返回此（partialy）：

2011-10-05 09:40:00.000 20 
2011-10-05 09:40:01.000 20 
2011-10-05 09:40:02.000 20 
2011-10-05 09:40:03.000 21 
2011-10-05 09:40:04.000 21 
2011-10-05 09:40:05.000 21 
2011-10-05 09:40:06.000 21 
2011-10-05 09:40:07.000 21 
2011-10-05 09:40:08.000 21 
2011-10-05 09:40:09.000 21 
2011-10-05 09:40:10.000 20 
2011-10-05 09:40:11.000 20 
2011-10-05 09:40:12.000 19 
2011-10-05 09:40:13.000 19 
2011-10-05 09:40:14.000 19 
2011-10-05 09:40:15.000 19 
2011-10-05 09:40:16.000 19 
2011-10-05 09:40:17.000 19 
2011-10-05 09:40:18.000 19 
2011-10-05 09:40:19.000 19 
2011-10-05 09:40:20.000 18 
2011-10-05 09:40:21.000 18 
2011-10-05 09:40:22.000 18 
2011-10-05 09:40:23.000 18 
2011-10-05 09:40:24.000 18 
2011-10-05 09:40:25.000 18 
2011-10-05 09:40:26.000 18 
2011-10-05 09:40:27.000 18 
2011-10-05 09:40:28.000 18 
2011-10-05 09:40:29.000 18 
2011-10-05 09:40:30.000 18 
2011-10-05 09:40:31.000 18 
2011-10-05 09:40:32.000 18 
2011-10-05 09:40:33.000 18 
2011-10-05 09:40:34.000 18 
2011-10-05 09:40:35.000 19 
2011-10-05 09:40:36.000 18 
2011-10-05 09:40:37.000 18 
2011-10-05 09:40:38.000 18 
2011-10-05 09:40:39.000 18 
2011-10-05 09:40:40.000 18 
2011-10-05 09:40:41.000 18 
2011-10-05 09:40:42.000 18 
2011-10-05 09:40:43.000 18 
2011-10-05 09:40:44.000 19 
2011-10-05 09:40:45.000 19 
2011-10-05 09:40:46.000 19 
2011-10-05 09:40:47.000 19 
2011-10-05 09:40:48.000 19 
2011-10-05 09:40:49.000 19 
2011-10-05 09:40:50.000 19 
2011-10-05 09:40:51.000 19 
2011-10-05 09:40:52.000 19 
2011-10-05 09:40:53.000 19 
2011-10-05 09:40:54.000 19 
2011-10-05 09:40:55.000 19 
2011-10-05 09:40:56.000 19 
2011-10-05 09:40:57.000 19 
2011-10-05 09:40:58.000 20 
2011-10-05 09:40:59.000 20 
2011-10-05 09:41:00.000 20 
2011-10-05 09:41:01.000 20 
2011-10-05 09:41:02.000 20 
2011-10-05 09:41:03.000 20 
2011-10-05 09:41:04.000 20 
2011-10-05 09:41:05.000 20 
2011-10-05 09:41:06.000 20 
2011-10-05 09:41:07.000 20 
2011-10-05 09:41:08.000 20 
2011-10-05 09:41:09.000 19 
2011-10-05 09:41:10.000 19 
2011-10-05 09:41:11.000 19 
2011-10-05 09:41:12.000 19 
2011-10-05 09:41:13.000 19 
2011-10-05 09:41:14.000 19 
2011-10-05 09:41:15.000 19 
2011-10-05 09:41:16.000 20 
2011-10-05 09:41:17.000 20 
2011-10-05 09:41:18.000 20 
2011-10-05 09:41:19.000 20 
2011-10-05 09:41:20.000 20 
2011-10-05 09:41:21.000 20 
2011-10-05 09:41:22.000 20 
2011-10-05 09:41:23.000 20 
2011-10-05 09:41:24.000 20 
2011-10-05 09:41:25.000 20 
2011-10-05 09:41:26.000 20 
2011-10-05 09:41:27.000 20 
2011-10-05 09:41:28.000 20 
2011-10-05 09:41:29.000 20 
2011-10-05 09:41:30.000 19 
2011-10-05 09:41:31.000 19 
2011-10-05 09:41:32.000 19 
2011-10-05 09:41:33.000 19 
2011-10-05 09:41:34.000 20 
2011-10-05 09:41:35.000 20 
2011-10-05 09:41:36.000 20 
2011-10-05 09:41:37.000 19 
2011-10-05 09:41:38.000 19 
2011-10-05 09:41:39.000 19 
2011-10-05 09:41:40.000 19 
2011-10-05 09:41:41.000 19 
2011-10-05 09:41:42.000 19 
2011-10-05 09:41:43.000 19 
2011-10-05 09:41:44.000 19 
2011-10-05 09:41:45.000 19 
2011-10-05 09:41:46.000 18 
2011-10-05 09:41:47.000 18 
2011-10-05 09:41:48.000 19 
2011-10-05 09:41:49.000 20 
2011-10-05 09:41:50.000 20 
2011-10-05 09:41:51.000 20 
2011-10-05 09:41:52.000 20 
2011-10-05 09:41:53.000 20 

所以我得到了很好的结果，但查询速度极其缓慢，我已经完成了索引，我只是想知道是否还有更多的事情可以做..

Answer 1

这是一个有趣的笛卡尔，你会在这里创建。

Select dt,count(1) 
from calview 
left join calls on calls.AnsweredTimestamp <= calview.dt AND 
        calls.ReleasedTimestamp >= calview.dt 
WHERE dt >='2011-10-05' 
and dt <'2011-10-06' 
group by dt 

我相信这应该给你一行每秒的呼叫是活动......那么这是一个简单的计数。希望我的语法是正确的，我没有一个MS SQL服务器环境来确认。

ETA：使用了左连接，因此带0个调用的任何秒都会出现在这里，并且空计数。如果切换到内部联接，则该行将在1秒内消失。