Class::DBI and multiple foreign keys

silent11 has asked for the wisdom of the Perl Monks concerning the following question:

After spending about an hour attempting to figure out why Class::DBI was croaking on a package that was defining a table with 2 foreign keys I realized that multiple foreign keys in one table isn't supported by Class::DBI.

Well, that's fine -- I'm just giving CDBI a test run, and I'm glad I found this little quirk out early in my usage with it.

In this test application (a bookmarks/links app) I had 3 tables, `users`, `category`, and `links`. The link table contained the columns `id`,`category_id`,`user_id`,`url`,etc...

My question is, why are multiple foreign keys such an evil thing? And what would be a better way to design this schema?

Update:Okay, I got it working, despite the problme I *thought* I had. reading this helped me out.

-silent11
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Janitored by Arunbear - moved from Meditations to SOPW. Also removed 'OT?' prefix from title.

Comment on Class::DBI and multiple foreign keys

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Re: Class::DBI and multiple foreign keys
by perrin (Chancellor) on May 31, 2005 at 01:58 UTC

Sounds like you got confused between multi-column foreign keys and multiple foreign keys in one table. Class::DBI does not support the former, although not for any special reason -- it simply hasn't been built yet.

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Re^2: Class::DBI and multiple foreign keys

by merlyn (Sage) on May 31, 2005 at 12:11 UTC

it simply hasn't been built yet.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

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Re: Class::DBI and multiple foreign keys
by monarch (Priest) on May 31, 2005 at 04:42 UTC

(this is just an aside comment)

After reading an article on www.perl.com I was quite enthusiastic about Class::DBI and wanted to use it for projects, however trying to install it was somewhat difficult - it had numerous dependancies and took me quite a while to get going.

One other package is like this: DateTime. I once went on a world trip and using this fantastic module I calculated the local times, and sunrises and sunsets on each day in each city that I would be in! Fabulous! However installing this module is a huge effort because of the sheer number of dependencies.

It is sad because I would like to use these modules more often but just fear for needing to run my application on a system where installing a large number of modules may not be an option (such as websites).

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Re^2: Class::DBI and multiple foreign keys

by PodMaster (Abbot) on May 31, 2005 at 05:40 UTC

However installing this module is a huge effort because of the sheer number of dependencies.

MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
** The third rule of perl club is a statement of fact: pod is sexy.

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