核心数据/数据库实体关系
如果存在两个实体，并且在某种意义上它们具有一对多关系，而在另一种意义上它们具有多对一关系。这 2 种关系是否会成为多对多关系，或者是否可以拥有 2 种关系？一对多，多对一？
If two entities exist and in one sense they have a one to many relationship and in another sense they have a many to one relationship. Do these 2 relationships become a many to many or is it ok to have 2 relationships? One to many, Many to one?
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这是一对多关系，给定您的示例 - 取决于您从关系的哪一侧开始它是一对多（GPS 位置 -> 照片）或多对一（照片 -> GPS 位置） ) - 但这并不意味着它是多对多！
一张照片有唯一一个 GPS 位置，因此您的表格将如下所示......
It's a one-to-many relationship, given your example - depending on which side of the relationship you start from it's one-to-many (GPS location -> photo) or many-to-one (photo -> GPS location) - this doesn't make it a many-to-many, though!
A photo has one-and-only-one GPS location, so your tables would look like this...
在 ER 建模中，两种实体类型之间存在多种关系是很正常且允许的。
In ER modelling it is quite normal and permissable for two entity types to have more than one relatiomship between them.