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  #1 (permalink)  
Old 04-28-11, 08:24
maximus___ maximus___ is offline
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multiple relations between two tables

I read all threats about multiple relations on the forum. but I did not find answer my question.

I want to design a petition database,
entities;
"user" & "petition"

relations;
1) compose: "users can compose several petitions. every petition must belong to one user"
2) sign: "users can sign any petition for one time. a petition can include several user sign"

I do something but I feel there is something wrong... (you can see it attached image)

my questions;
1) how must be the tables and relations in this case?
2) do you know complete example about petition database?

If you could guide me, I will be very happy

sorry for my bad english.
thank you
Attached Thumbnails
multiple relations between two tables-db.png  
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Old 04-28-11, 08:52
r937 r937 is offline
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that model looks okay to me

why do you feel there is something wrong?

by the way, your english is fine
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Old 04-28-11, 09:16
maximus___ maximus___ is offline
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thank you for your answer dear r937,

I dont know. I am very newbie about database design...
Only feeling. I am not sure if its possible to define multible relations like this.
I do not want to face some problems while I run sql queries..

you said that multiple relations like this is possible and in accordance with database design consept and rules...?

thank you again...
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Old 04-28-11, 09:41
r937 r937 is offline
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Quote:
Originally Posted by maximus___ View Post
you said that multiple relations like this is possible and in accordance with database design consept and rules...?
yes

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Old 04-28-11, 09:50
maximus___ maximus___ is offline
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thank you very much dear r937
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