我要感谢最近帮助过我的人。我已经非常接近我的目标,但我在编码知识方面一直遇到一些障碍。我有创建此表的代码,但 CSHOW 列出现错误。
| SHOW_DATE | SONG_ORDER | SHOW_ID | SONG_NAME | SONG_ID | PREVDATE | CSHOW |
-------------------------------------------------------------------------------
| 07/19/13 | 1 | 899 | Song Name A | 51 | 04/10/13 | 7 |
| 07/19/13 | 2 | 899 | Song Name D | 568 | NEW SONG | 7 |
| 07/19/13 | 3 | 899 | Song Name C | 168 | 04/10/13 | 7 |
| 07/19/13 | 4 | 899 | Song Name E | 13 | 03/03/13 | 7 |
这是通过查询此数据和代码找到的:
CREATE TABLE tbl_songs
(`song_id` int, `song_name` varchar(11));
INSERT INTO tbl_songs
(`song_id`, `song_name`)
VALUES
(51, 'Song Name A'),
(368, 'Song Name B'),
(168, 'Song Name C'),
(568, 'Song Name D'),
(13, 'Song Name E');
CREATE TABLE tbl_shows
(`song_id` int, `song_order` int, `show_date` datetime, `show_id` int)
;
INSERT INTO tbl_shows
(`song_id`, `song_order`, `show_date`, `show_id`)
VALUES
(51, 1, '2013-07-19 00:00:00', 899),
(568, 2, '2013-07-19 00:00:00', 899),
(168, 3, '2013-07-19 00:00:00', 899),
(13, 4, '2013-07-19 00:00:00', 899),
(368, 1, '2013-07-06 00:00:00', 898),
(368, 1, '2013-07-03 00:00:00', 897),
(368, 1, '2013-05-27 00:00:00', 896),
(51, 1, '2013-04-10 00:00:00', 895),
(168, 1, '2013-04-10 00:00:00', 895),
(513, 1, '2013-03-12 00:00:00', 894),
(13, 1, '2013-03-03 00:00:00', 893);
代码
SELECT DATE_FORMAT(a.show_date,'%m/%d/%y') as show_date, a.song_order, a.show_id,
b.song_name, a.song_id, (
SELECT
IFNULL(MAX(DATE_FORMAT(show_date,'%m/%d/%y')), 'NEW SONG')
FROM tbl_shows AS c
WHERE a.show_date > c.show_date and a.song_id = c.song_id
) As PrevDate,
(
SELECT
COUNT(*) FROM tbl_shows AS d
where a.show_date > d.show_date
) As cShow
FROM tbl_shows a, tbl_songs b
WHERE a.song_id = b.song_id
AND a.show_id = 899
我正在计算每首歌曲在 Show_Date 和 PrevDate 之间播放了多少节目......并为该行返回该值。谁能指出我正确的方向?谢谢你。SQLFiddle http://sqlfiddle.com/#!2/57d96/34