所以我的查询:
SELECT a.term_id,
a.update_date,
a.campus,
a.last_hour,
a.enrolled_this_hour,
-- (SELECT SUM(a.enrolled_this_hour)
-- FROM term_enrollment_by_hour h3
-- WHERE a.term_id = h3.term_id
-- AND h3.update_date = a.update_date
-- GROUP BY h3.campus
-- ) as attempt
FROM (SELECT h1.term_id,
update_date,
this_hour,
campus,
last_hour,
enrolled_this_hour
FROM term_enrollment_by_hour h1
LEFT OUTER JOIN
term_enrollment_by_hour h2
ON h1.term_id = h2.term_id
AND h1.campus = h2.campus
ORDER BY h1.update_date, h1.update_hour, h1.campus) a;
返回类似于此的数据集:
term update_date campus last_hour enrolled
14FALL 10/03/14 WEST 06:00 15
14FALL 10/03/14 NORT 06:00 5
14FALL 10/03/14 EAST 06:00 30
14FALL 10/03/14 WEST 07:00 15
14FALL 10/03/14 NORT 07:00 5
14FALL 10/03/14 EAST 07:00 30
14FALL 10/04/14 WEST 08:00 20
14FALL 10/04/14 NORT 08:00 10
14FALL 10/04/14 EAST 08:00 50
14FALL 10/04/14 WEST 08:00 20
14FALL 10/04/14 NORT 08:00 10
14FALL 10/04/14 EAST 08:00 50
如果可能的话,我想添加一个按天和校园分组的列,但似乎无法正确汇总。以下是我希望数据的样子:
term update_date campus last_hour enrolled group_attempt
14FALL 10/03/14 WEST 06:00 15 30
14FALL 10/03/14 NORT 06:00 5 10
14FALL 10/03/14 EAST 06:00 30 60
14FALL 10/03/14 WEST 07:00 15 30
14FALL 10/03/14 NORT 07:00 5 10
14FALL 10/03/14 EAST 07:00 30 60
14FALL 10/04/14 WEST 08:00 20 40
14FALL 10/04/14 NORT 08:00 10 20
14FALL 10/04/14 EAST 08:00 50 100
14FALL 10/04/14 WEST 08:00 20 40
14FALL 10/04/14 NORT 08:00 10 20
14FALL 10/04/14 EAST 08:00 50 100
提前感谢您的帮助,如果需要更多信息,我很乐意提供。