# Triple relationship **URL:** \ **Category:** Rails\ **Created:** [April 1, 2006, 11:29am UTC](https://www.ruby-forum.com/t/triple-relationship/56584 "2006-04-01T11:29:53Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![vanesam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/7993a0/32.png) [@vanesam](https://www.ruby-forum.com/u/vanesam)\ **Post date:** [April 1, 2006, 11:29am UTC](https://www.ruby-forum.com/t/triple-relationship/56584/1 "2006-04-01T11:29:53Z")
Hi list, I need to represent a relationship between three tables: Tags (id, name) Users (id, name, email, … ) Documents (id, title, … ) I created a forth table called Assignments(id, tag-id, user-id, document-id, date). I have couple of questions: Should I use belongs-to and has-many to capture this? If so, How can I do that? should I have the id as the primary key in Assignment table or not? Any help is most appreciated. Thanks, -Vanesa ---
**Author:** ![vanesam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/7993a0/32.png) [@vanesam](https://www.ruby-forum.com/u/vanesam)\ **Post date:** [April 1, 2006, 12:29pm UTC](https://www.ruby-forum.com/t/triple-relationship/56584/2 "2006-04-01T12:29:49Z")
If you are attempting to implement tagging functionality on your documents then you should try to use acts\_as\_taggable gem or acts\_as\_taggable plugin. (I used gem in my use case, because it was more mature). Chances are that you want to users to be able to tag documents? if thats the case then using acts\_as\_taggable gem will make your life easy. get back to me, if that is the case I can guide you further. Anu ----- Original Message ---- From: vanesam [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) To: removed\_email\_address@domain.invalid Sent: Saturday, April 1, 2006 1:29:53 AM Subject: [Rails] Triple relationship Hi list, I need to represent a relationship between three tables: Tags (id, name) Users (id, name, email, … ) Documents (id, title, … ) I created a forth table called Assignments(id, tag-id, user-id, document-id, date). I have couple of questions: Should I use belongs-to and has-many to capture this? If so, How can I do that? should I have the id as the primary key in Assignment table or not? Any help is most appreciated. Thanks, -Vanesa ---
**Author:** ![vanesam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/7993a0/32.png) [@vanesam](https://www.ruby-forum.com/u/vanesam)\ **Post date:** [April 1, 2006, 6:21pm UTC](https://www.ruby-forum.com/t/triple-relationship/56584/3 "2006-04-01T18:21:55Z")
On Sat, Apr 01, 2006 at 11:29:53AM +0200, vanesam wrote: } Hi list, } } I need to represent a relationship between three tables: } } Tags (id, name) } Users (id, name, email, … ) } Documents (id, title, … ) } } I created a forth table called Assignments(id, tag-id, user-id, } document-id, date). } I have couple of questions: } Should I use belongs-to and has-many to capture this? If so, How can I } do that? } should I have the id as the primary key in Assignment table or not? Tags has\_many Assignments Users has\_many Assignments Documents has\_many Assignments Assignments belongs\_to Tag, User, Document Someone mentioned acts\_as\_taggable, which only really makes sense if a single Assignment (or other model) has zero or more tags, rather than the single tag you seem to be indicating. } Any help is most appreciated. } Thanks, } -Vanesa –Greg ---
**Author:** ![vanesam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/7993a0/32.png) [@vanesam](https://www.ruby-forum.com/u/vanesam)\ **Post date:** [April 1, 2006, 9:41pm UTC](https://www.ruby-forum.com/t/triple-relationship/56584/4 "2006-04-01T21:41:14Z")
Hi, I want the user to be able to tag the documents that exist in the system…also I like the system (the database) to keep track of “who tagged what with which tag and when”. I am new to both Ruby and Rails and don’t have that much experince any help is appreciated. Thanks, -Vanesa unknown wrote: > If you are attempting to implement tagging functionality on your > documents then you should try to use acts\_as\_taggable gem or > acts\_as\_taggable plugin. (I used gem in my use case, because it was more > mature). > > Chances are that you want to users to be able to tag documents? if thats > the case then using acts\_as\_taggable gem will make your life easy. get > back to me, if that is the case I can guide you further. > > Anu > > ----- Original Message ---- > From: vanesam [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) > To: removed\_email\_address@domain.invalid > Sent: Saturday, April 1, 2006 1:29:53 AM > Subject: [Rails] Triple relationship > > Hi list, > > I need to represent a relationship between three tables: > > Tags (id, name) > Users (id, name, email, … ) > Documents (id, title, … ) > > I created a forth table called Assignments(id, tag-id, user-id, > document-id, date). > I have couple of questions: > Should I use belongs-to and has-many to capture this? If so, How can I > do that? > should I have the id as the primary key in Assignment table or not? > > Any help is most appreciated. > > Thanks, > -Vanesa ---
**Author:** ![vanesam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/7993a0/32.png) [@vanesam](https://www.ruby-forum.com/u/vanesam)\ **Post date:** [April 2, 2006, 2:35am UTC](https://www.ruby-forum.com/t/triple-relationship/56584/5 "2006-04-02T02:35:43Z")
El sáb, 01-04-2006 a las 21:41 +0200, vanesa mirzaee escribió: > Hi, > > I want the user to be able to tag the documents that exist in the > system…also I like the system (the database) to keep track of “who > tagged what with which tag and when”. > I am new to both Ruby and Rails and don’t have that much experince any > help is appreciated. Hi Vanesa, You can use UserStamp Plugin [http://www.delynnberry.com/pages/userstamp/](http://www.delynnberry.com/pages/userstamp/) Copy&Paste from userstamp description: “The Userstamp Plugin extends ActiveRecord::Base to add automatic updating of created\_by and updated\_by attributes of your models in much the same way that the ActiveRecord::Timestamp module updates created\_(at/on) and updated\_(at/on) attributes.” Cheers! Juanjo ---
**Author:** ![vanesam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/7993a0/32.png) [@vanesam](https://www.ruby-forum.com/u/vanesam)\ **Post date:** [April 4, 2006, 7:05am UTC](https://www.ruby-forum.com/t/triple-relationship/56584/6 "2006-04-04T07:05:39Z")
vanesa mirzaee wrote: > Hi, > > I want the user to be able to tag the documents that exist in the > system…also I like the system (the database) to keep track of “who > tagged what with which tag and when”. > I am new to both Ruby and Rails and don’t have that much experince any > help is appreciated. It seems to me you want a habtm relationship between documents and tags. In your joining table you should store doc\_id, tag\_id and user\_id. And as you are building your tags ensure to properly set the user\_id attribute (check the rails api for has\_and\_belongs\_to\_many to find out how this is done) Then you can get all tags from your document by saying document.tags, or all documents that are tagged with something like by saying tag.documents and lastly, to get all user.tags just add a tags method in your users model like this: def tags Tag.find\_by\_sql([“SELECT \* FROM tags, documents\_tags WHERE documents\_tags.user\_id = ? AND tags.id = documents\_tags.tag\_id”], self.id) end – Bryan Buecking