我有一个基于 CTE 的查询,我向其中传递了大约 2600 个 4 元组纬度/经度值 - 这些值已被 ID 标记并保存在名为坐标的第二个表中。这些左上角和右下角的纬度/经度值被传递到 CTE,以显示给定两个时间戳在这些坐标内发出的请求量(每小时)。
但是,我想在给定的时间戳内获得每天的总请求数。也就是说,我想获取每个指定日期的用户请求总数。例如,用户选择每周三或周三和周四等查看 - 2012 年 1 月 1 日至 16 日期间的 11:55 至 22:04 之间,我通过的每个纬度/经度 4 元组。输出基本上是这样的:
coordinates_id | stamp | zcount
1 Jan 4 2012 200 (total requests on Wednesday Jan 4 between 11:55 and 22:04)
1 Jan 11 2012 121 (total requests on Wednesday Jan 11 between 11:55 and 22:04)
2 Jan 4 2012 255 (total requests on Wednesday Jan 4 between 11:55 and 22:04)
2 Jan 11 2012 211 (total requests on Wednesday Jan 11 between 11:55 and 22:04)
.
.
.
我该怎么做?我的查询如下:
WITH v AS (
SELECT '2012-01-1 11:55:11'::timestamp AS _from -- provide times once
,'2012-01-16 22:02:21'::timestamp AS _to
)
, q AS (
SELECT c.coordinates_id
, date_trunc('hour', t.calltime) AS stamp
, count(*) AS zcount
FROM v
JOIN mytable t ON t.calltime BETWEEN v._from AND v._to
AND (t.calltime::time >= v._from::time AND
t.calltime::time <= v._to::time) AND
(extract(DOW from t.calltime) = 3)
JOIN coordinates c ON (t.lat, t.lon)
BETWEEN (c.bottomrightlat, c.topleftlon)
AND (c.topleftlat, c.bottomrightlon)
GROUP BY c.coordinates_id, date_trunc('hour', t.calltime)
)
, cal AS (
SELECT generate_series('2011-2-2 00:00:00'::timestamp
, '2012-4-1 05:00:00'::timestamp
, '1 hour'::interval) AS stamp
FROM v
)
SELECT q.coordinates_id, cal.stamp, COALESCE (q.zcount, 0) AS zcount
FROM v, cal
LEFT JOIN q USING (stamp)
WHERE (extract(hour from cal.stamp) >= extract(hour from v._from) AND
extract(hour from cal.stamp) <= extract(hour from v._to)) AND
(extract(DOW from cal.stamp) = 3)
AND cal.stamp >= v._from AND cal.stamp <= v._to
GROUP BY q.coordinates_id, cal.stamp, q.zcount
ORDER BY q.coordinates_id ASC, stamp ASC;
它产生的样本结果是这样的:
coordinates_id | stamp | zcount
1 2012-01-04 16:00:00 1
1 2012-01-04 19:00:00 1
1 2012-01-11 14:00:00 1
1 2012-01-11 17:00:00 1
1 2012-01-11 19:00:00 1
2 2012-01-04 16:00:00 1
因此,正如我上面提到的,我希望将其视为
coordinates_id | stamp | zcount
1 2012-01-04 2
1 2012-01-11 3
2 2012-01-04 1