Database Design - Best way to manage these relationships

I am working on a project (based in Django although that's not really relevant to my question) and I am struggling to work out the best way to represent the data models.

I have the four following models:

User, Client, Meeting, Location

User and Client have a many-to-many relationship through the Meeting model. The Meeting model has a one-to-one relationship with the Location model.

Meetings will take place at either:

1. The address defined in the User (or UserProfile) model
2. The address defined in the Client model.
3. Some other location which has to be defined at a later date.

I'm struggling to work out the best way to store the Location data in order to make it as clean and reusable as possible.

• I considered making Location as a field in the Meetings model rather than a model in its own right - although this could also lead to redundant data if lots of Meetings are created at the same location, so this is probably a non-starter.

• I could automatically create Location records for each User and Client that gets created and use a generic relationship between the relevant records, however, I understand th开发者_运维问答at this can lead to inefficient database performance. Also, not every Client / User would be able to hold meetings at their Location.

Can anyone see an tidier alternative?

Any advice appreciated.

Thanks.

I considered making Location as a field in the Meetings model rather than a model in its own right - although this could also lead to redundant data if lots of Meetings are created at the same location, so this is probably a non-starter.

No, that's a really good thought, because it points you straight at the real problem.

The real problem is that there's a difference between a meeting and the parties that attend a meeting. A meeting has some attributes that have nothing to do with the attendees: it has at the very least a time and a place.

So I think you should change your thinking about the Meeting model.

Instead of users having a M:N relationship with clients through the Meeting model, they should have a M:N relationship through, say, an Attendance model. (A Registration or Reservation or MightAttend model might be more appropriate for you.) And the Meeting model should change to reflect the unique attributes of a real-world meeting: time and place.

I would expect Meetings and Locations to have a many-to-one relationship. Can't a location be used for more than one meeting? (at different times, of course)

It seems to me that a location has attributes that persist beyond its use for a single meeting. Example: seating capacity.