Hi Guys, When you use ActiveRecord relationship, there is always a place to put foreign key on your table, e.g., id and foo_id. However, from rails perspective, foreign keys are not required as long as data could be associated. I would like know your design decision on database foreign keys. Is it better to have it? Or just leave it to speed up your development? Thanks, Glenn --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Glenn wrote:> Hi Guys, > > When you use ActiveRecord relationship, there is always a place to put > foreign key on your table, e.g., id and foo_id. However, from rails > perspective, foreign keys are not required as long as data could be > associated. > > I would like know your design decision on database foreign keys. Is > it better to have it? Or just leave it to speed up your development? > > Thanks, > GlennGlenn, Are you referring to "foreign keys" or "foreign key constraints"? The former is certainly needed by ActiveRecord/Rails for any non trivial relationship between 2 tables. Leaving out foreign keys is not even an option when working with relational entities. Perhaps you meant foreign key constraints? Currently, their use requires that you know vendor specific details of your db (which is not usually a concern for most). Anyways, in my opinion, you are right in that you can usually omit them until your DBA comes back from vacation or you wake up in a pool of sweat knowing that you could have done more to protect the integrity of your data. HtH ilan -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Ilan Berci wrote:> Glenn wrote: >> When you use ActiveRecord relationship, there is always a place to put >> foreign key on your table, e.g., id and foo_id. However, from rails >> perspective, foreign keys are not required as long as data could be >> associated. >> >> I would like know your design decision on database foreign keys. Is >> it better to have it? Or just leave it to speed up your development? > > Are you referring to "foreign keys" or "foreign key constraints"? The > former is certainly needed by ActiveRecord/Rails for any non trivial > relationship between 2 tables. Leaving out foreign keys is not even an > option when working with relational entities. > > Perhaps you meant foreign key constraints? Currently, their use > requires that you know vendor specific details of your db (which is not > usually a concern for most). Anyways, in my opinion, you are right in > that you can usually omit them until your DBA comes back from vacation > or you wake up in a pool of sweat knowing that you could have done more > to protect the integrity of your data.If you want some level of integrity but don''t want to stick the constraints in the DB, you could use this: http://blog.hasmanythrough.com/2007/7/14/validate-your-existence It does something pretty close to fk constraints using Rails validations. -- Josh Susser http://blog.hasmanythrough.com -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
El Jul 27, 2007, a las 9:06 PM, Glenn escribió:> I would like know your design decision on database foreign keys. Is > it better to have it? Or just leave it to speed up your development?I normally use them via this plugin: http://www.redhillonrails.org/#foreign_key_migrations You get indices as a side-effect (don''t know whether that applies to all databases) and they help getting your :dependents right in has_* declarations. -- fxn --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe@googlegroups.com For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Hi Everyone, Thank you very much for your postings. It really helped me to start a new project. Ilan, Thanks for your clarification of the terminology. Yes, I was wondering if foreign key constrain should be defined on database level. As Josh pointed, it we can check referential integrity on application level. We used to use database for everything such as managing transaction, validating data, user authentication, etc. However, it appears that current trend is to put most staff in application level and let database to take care persistence only. My work place still have lots of legacy applications sitting top of of the database. It would be good idea to have constrains in both application and database. Xavier, thank you so much for showing me a nice plugin. I will definatelly look into the plugin. It''s will be very nice to have automated solution for creating foreign key constrains. Glenn --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---