我正在使用PHP和PDO,我需要重新识别连接3个表的信息:
该表具有以下结构:
相片:
photo_id (int) path (varchar) nick (varchar) date (timestamp)
专辑
album_id (int) album_name (varchar) nick (varchar) date (timestamp)
album_photos
album_id (int) photo_id (int) nick (varchar) date (timestamp)
因此,我想显示所有相册,每张相册最多包含5张照片, 用户昵称是“所有者” 。
如下所示:
album_name_1: [photo_1] [photo_2] [photo_3] [photo_4] [photo_5] album_name_2: [photo_1] [photo_2] [photo_3] [photo_4] [photo_5]
我只知道可以使用INNER JOIN来制作类似的东西,但是我找不到如何用3个桌子来制作它。
有例子或其他帮助我可以做到这一点吗?
SELECT a., c.date FROM Album a INNER JOIN Album_Photo b ON a.Album_ID = b.Album_ID INNER JOIN Photo c ON b.Photo_ID = c.Photo_ID WHERE c.Nick = ‘owner’ AND ( SELECT COUNT() FROM album_photo d WHERE b.album_id = d.album_id AND d.nick = ‘owner’ AND b.date >= d.date ) <= 2 // <<== change this value to 5