我有一个歌曲表，有的歌曲是专辑歌曲，有的是单曲... 我有一张专辑表...
示例:
如果专辑ID为[null]，则表示歌曲为单曲
歌曲表:
+--------+---------+-----------+----------------+---------+---------------+-------+--------+--------+------+-------+-------+----------+
| Row ID | Song ID | Album ID | Song Name | Band | Date Released | Genre | Lyrics | Lenght | Size | Plays | Likes | Dislikes |
+--------+---------+-----------+----------------+---------+---------------+-------+--------+--------+------+-------+-------+----------+
| 1 | Song-01 | Album-1 | Song-001 | Band-1 | 2010-12-15 | Rock | ... | 4:30 | 4 MB | 101 | 11 | 1 |
| 2 | Song-02 | Album-1 | Song-002 | Band-1 | 2010-12-15 | Rock | ... | 5:30 | 5 MB | 102 | 12 | 2 |
| 3 | Song-03 | Album-1 | Song-003 | Band-1 | 2010-12-15 | Rock | ... | 3:30 | 3 MB | 103 | 13 | 3 |
| 4 | Song-04 | [null] | Song-004 | Band-1 | 2010-12-16 | Rock | ... | 4:30 | 4 MB | 104 | 14 | 4 |
| 5 | Song-05 | Album-2 | Song-005 | Band-1 | 2010-12-17 | POP | ... | 3:30 | 3 MB | 105 | 15 | 5 |
| 6 | Song-06 | Album-2 | Song-006 | Band-1 | 2010-12-17 | RAP | ... | 5:30 | 5 MB | 106 | 16 | 6 |
| 7 | Song-07 | [null] | Song-007 | Band-2 | 2010-12-17 | Rock | ... | 3:30 | 3 MB | 107 | 17 | 7 |
| 8 | Song-08 | Album-3 | Song-008 | Band-2 | 2010-12-17 | Rock | ... | 4:30 | 4 MB | 108 | 18 | 8 |
| 9 | Song-09 | Album-3 | Song-009 | Band-2 | 2010-12-17 | POP | ... | 5:30 | 5 MB | 109 | 19 | 9 |
| 10 | Song-10 | Album-3 | Song-010 | Band-2 | 2010-12-17 | Punk | ... | 6:30 | 6 MB | 110 | 20 | 0 |
| 11 | Song-11 | Album-3 | Song-011 | Band-2 | 2010-12-17 | RAP | ... | 7:30 | 7 MB | 111 | 21 | 1 |
| 12 | Song-12 | [null] | Song-012 | Band-2 | 2010-12-18 | Rock | ... | 3:30 | 3 MB | 112 | 22 | 2 |
| 13 | Song-13 | [null] | Song-013 | Band-2 | 2010-12-18 | Rock | ... | 2:30 | 2 MB | 113 | 23 | 3 |
| 14 | Song-14 | [null] | Song-014 | Band-3 | 2010-12-18 | Rock | ... | 6:30 | 6 MB | 114 | 24 | 4 |
| 15 | Song-15 | [null] | Song-015 | Band-3 | 2010-12-19 | Rock | ... | 7:30 | 7 MB | 115 | 25 | 5 |
| 16 | Song-16 | [null] | Song-016 | Band-3 | 2010-12-19 | Rock | ... | 4:30 | 4 MB | 116 | 26 | 6 |
| 17 | Song-17 | [null] | Song-017 | Band-4 | 2010-12-19 | POP | ... | 3:30 | 3 MB | 117 | 27 | 7 |
| 18 | Song-18 | [null] | Song-018 | Band-4 | 2010-12-19 | POP | ... | 2:30 | 2 MB | 118 | 28 | 8 |
| 19 | Song-19 | [null] | Song-019 | Band-5 | 2010-12-20 | Rock | ... | 4:30 | 4 MB | 119 | 29 | 9 |
| 20 | Song-20 | [null] | Song-020 | Band-5 | 2010-12-20 | Rock | ... | 5:30 | 5 MB | 120 | 30 | 0 |
| 21 | Song-21 | [null] | Song-021 | Band-5 | 2010-12-20 | Rock | ... | 6:30 | 6 MB | 121 | 31 | 1 |
| 22 | Song-22 | Album-4 | Song-022 | Band-5 | 2010-12-21 | Rock | ... | 3:30 | 3 MB | 122 | 32 | 2 |
| 23 | Song-23 | Album-4 | Song-023 | Band-5 | 2010-12-21 | Rock | ... | 2:30 | 2 MB | 123 | 33 | 3 |
| 24 | Song-24 | Album-4 | Song-024 | Band-5 | 2010-12-21 | Rock | ... | 4:30 | 4 MB | 124 | 34 | 4 |
| 25 | Song-25 | [null] | Song-025 | Band-6 | 2010-12-22 | Rock | ... | 5:30 | 5 MB | 125 | 35 | 5 |
| 26 | Song-26 | [null] | Song-026 | Band-6 | 2010-12-22 | Rock | ... | 6:30 | 6 MB | 126 | 36 | 6 |
| 27 | Song-27 | Album-5 | Song-027 | Band-7 | 2010-12-22 | POP | ... | 4:30 | 4 MB | 127 | 37 | 7 |
| 28 | Song-28 | Album-5 | Song-028 | Band-7 | 2010-12-22 | PUNK | ... | 3:30 | 3 MB | 128 | 38 | 8 |
| 29 | Song-29 | [null] | Song-029 | Band-7 | 2010-12-23 | Rock | ... | 2:30 | 2 MB | 129 | 39 | 9 |
| 30 | Song-30 | Album-6 | Song-030 | Band-8 | 2010-12-25 | Rock | ... | 5:30 | 5 MB | 130 | 40 | 0 |
+--------+---------+-----------+----------------+---------+---------------+-------+--------+--------+------+-------+-------+----------+
专辑表:
+--------+-----------+----------------+---------+---------------+-------------------+--------+-------+----------+
| Row ID | Album ID | Album Name | Band | Date Released | Genre | Lenght | Likes | Dislikes |
+--------+-----------+----------------+---------+---------------+-------------------+--------+-------+----------+
| 1 | Album-1 | Album One | Band-1 | 2010-12-15 | Rock | 13:30 | 101 | 31 |
| 2 | Album-2 | Album Two | Band-1 | 2010-12-17 | POP/RAP | 9:00 | 102 | 32 |
| 3 | Album-3 | Album Three | Band-2 | 2010-12-17 | Rock/Punk/POP/RAP | 24:00 | 103 | 33 |
| 4 | Album-4 | Album Four | Band-5 | 2010-12-21 | Rock | 10:30 | 104 | 34 |
| 5 | Album-5 | Album Five | Band-7 | 2010-12-22 | Punk/POP | 8:00 | 105 | 35 |
| 6 | Album-6 | Album Six | Band-8 | 2010-12-25 | Rock | 5:30 | 106 | 36 |
+--------+-----------+----------------+---------+---------------+-------------------+--------+-------+----------+
如果我只想拿最新的五张专辑和/或单曲 这意味着结果将是(从最新到最旧的顺序):
“名称”列是指“单曲名称或专辑名称”
第 1 页:
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Name | Band | Date Released | Genre | IsAlbum? | IsSingle? | Lyrics | Lenght | Size | Likes | Dislikes | Plays |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Album Six | Band-8 | 2010-12-25 | Rock | YES | NO | - | 5:30 | -- | 106 | 36 | - |
| Song 29 | Band-7 | 2010-12-23 | Rock | NO | YES | ... | 2:30 | 2 MB | 39 | 9 | 129 |
| Album Five | Band-7 | 2010-12-22 | Punk/POP | YES | NO | - | 8:00 | -- | 105 | 35 | - |
| Song 26 | Band-6 | 2010-12-22 | Rock | NO | YES | ... | 6:30 | 6 MB | 36 | 6 | 126 |
| song 25 | Band-6 | 2010-12-22 | Rock | NO | YES | ... | 5:30 | 5 MB | 35 | 5 | 125 |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
而且如果我只想取最近五张(上表中的那些)专辑和/或单曲之后的最新五张，结果将从最新到最旧排序:
第 2 页:
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Name | Band | Date Released | Genre | IsAlbum? | IsSingle? | Lyrics | Lenght | Size | Likes | Dislikes | Plays |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Album Four | Band-5 | 2010-12-21 | Rock | YES | NO | - | 10:30 | -- | 104 | 34 | - |
| Song 21 | Band-5 | 2010-12-20 | Rock | NO | YES | ... | 6:30 | 6 MB | 31 | 1 | 121 |
| Song 20 | Band-5 | 2010-12-20 | Rock | NO | YES | ... | 5:30 | 5 MB | 30 | 0 | 120 |
| Song 19 | Band-5 | 2010-12-20 | Rock | NO | YES | ... | 4:30 | 4 MB | 29 | 9 | 119 |
| song 18 | Band-4 | 2010-12-19 | POP | NO | YES | ... | 2:30 | 2 MB | 28 | 8 | 118 |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
他们之前的五个将是:
第 3 页:
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Name | Band | Date Released | Genre | IsAlbum? | IsSingle? | Lyrics | Lenght | Size | Likes | Dislikes | Plays |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Song 17 | Band-4 | 2010-12-19 | POP | NO | YES | ... | 3:30 | 3 MB | 27 | 7 | 117 |
| Song 16 | Band-3 | 2010-12-19 | Rock | NO | YES | ... | 4:30 | 4 MB | 26 | 6 | 116 |
| Song 15 | Band-3 | 2010-12-19 | Rock | NO | YES | ... | 5:30 | 5 MB | 25 | 5 | 115 |
| Song 14 | Band-3 | 2010-12-18 | Rock | NO | YES | ... | 6:30 | 6 MB | 24 | 4 | 114 |
| song 13 | Band-2 | 2010-12-18 | Rock | NO | YES | ... | 2:30 | 2 MB | 23 | 3 | 113 |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
还有前五个:
第 4 页:
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Name | Band | Date Released | Genre | IsAlbum? | IsSingle? | Lyrics | Lenght | Size | Likes | Dislikes | Plays |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Song 12 | Band-2 | 2010-12-18 | Rock | NO | YES | ... | 3:30 | 3 MB | 22 | 2 | 112 |
| Album Three | Band-2 | 2010-12-17 | Rock/Punk/POP/RAP | YES | NO | - | 24:00 | -- | 103 | 33 | - |
| Song 7 | Band-2 | 2010-12-17 | Rock | NO | YES | ... | 3:30 | 3 MB | 17 | 7 | 107 |
| Album Two | Band-1 | 2010-12-17 | POP/RAP | YES | NO | - | 9:00 | -- | 102 | 32 | - |
| song 4 | Band-1 | 2010-12-16 | Rock | NO | YES | ... | 4:30 | 4 MB | 14 | 4 | 104 |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
在最后一个表格(或页面)中:
第 5 页:
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Name | Band | Date Released | Genre | IsAlbum? | IsSingle? | Lyrics | Lenght | Size | Likes | Dislikes | Plays |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
| Album One | Band-1 | 2010-12-15 | Rock | YES | NO | - | 13:00 | -- | 101 | 31 | - |
+-----------------+---------+-----------------+-------------------+----------+-----------+--------+--------+------+-------+----------+-------+
但是，问题是当我这样做时，“LIMIT X , Y”中的 X 和 Y 不会是 X=0,Y=5 或 X=5,Y=5 或 X=10,Y =5 等等...
所以，我的问题是:我怎样才能在 PHP 和 SQL (MySQL) 中完成上述操作？
对不起我的英语 提前致谢
最佳答案
您弄错了 LIMIT 子句。它是 OFFSET,QUANTITY。您的示例查询一次获取 5 条记录，因此 QUANTITY 始终为 5，并且您将为每“页”结果将偏移量增加 5。
Top 5 songs/albums: LIMIT 0,5
Top 6-10 songs/album: LIMIT 5,5
Top 11-15 songs/albums: LIMIT 10,5
etc...
关于php - 在 PHP 和 MySQL 方面需要帮助，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/5557730/
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