How do I Relate these 4 Tables

Posted by Baddie on Stack Overflow See other posts from Stack Overflow or by Baddie
Published on 2009-11-19T22:55:40Z Indexed on 2010/04/06 22:13 UTC
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entity-framework

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entity-relationship

Trying to setup a simple Thread/Poll table mapping.

Here is what I have:

Threads table

ThreadID (Primary Key/Identity Column)

Polls table

PollID (Primary Key, FK for ThreadID for one-to-one relation)
Question

PollOptions table

PollOptionID (Identity/Primary Key)
Text
PollID

PollVotes table

PollVoteID (Primary Key/Identity)
PollOptionID

I'm not sure if this is a proper relationship. It seems wrong but I'm not sure whats wrong with it.

A Thread can have 0 or 1 Poll.

A Poll can have 2 or more PollOptions.

A PollOption can have 0 or many PollVotes.

I'm going to be using Entity Framework and before I generate the code for it (VS 2010, .NET 4) I want to make sure I have the proper relationship mapping.

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