Entity Relationship Diagram

Question

I'm trying to create a database but in the design process. A bit of background on what is required. I have a table containing a bunch of details concerning customers. This is being imported from an external csv file every month. The data is going to be validated checking the email is valid and then copied to another table in the exact same structure but containing the details that are valid (valid email).

This data being imported is from an online registration (including name, DOB, email) form where customers choose their favourite genre styles based on external data of a list of pre-selected genres. There about 11 genres (also in a csv file). Also in this imported customer data is what each customer has chosen as a recently purchased magazine. This also comes from a magazine csv file with list of the magazines and a contact detail at the publisher.

Using this data I want to based on the customer data link between the music genres and magazine lists for third party suppliers who can view mailing lists and potential customers.

I've attached a jpg file of the erd diagram. I'm having trouble make sure the links between entities are correct. http://img718.imageshack.us/i/erd2.jpg/

Answer 1

I think you're on the right track.

• Invalidated listeners to Listeners is 1 <-> 0..1
• Listeners to Genres: 0..n <-> 0..n

which can be represented as

• Listeners to Listener Genres: 1 <-> 0..n
• Listener Genres to Genres: 0..n <-> 1

and same thing for magazines