Rails: Multi-Column Primary Key for ActiveRecord

ruby-talk
1

Hello,

Is there a way to set an ActiveRecord object to point to a table with a
multi-column primary key?

Thank you,
Brian Takita

2

I get the impression that the current implementation does not support a
primary key with multiple columns.

Looking at base.rb, the primary_key variable is used in such a way that
a single column name is expected.

3

Is there a way to set an ActiveRecord object to point to a table with a
multi-column primary key?

Not really, no. Active Record was designed for a single column primary key and that assumption runs pretty deep. AR is not a Data Mapper, so you have to be within a reasonable vicinity of its assumptions to enjoy it.

ยทยทยท

--
David Heinemeier Hansson
http://www.loudthinking.com -- Broadcasting Brain
http://www.basecamphq.com -- Online project management
http://www.rubyonrails.com -- Web-application framework

4

This is regarding ActiveRecord 1.10.1

5

David,

First of all, your Rails framework is well done and has revamped my
interest in Ruby, which has been a very good thing. Thank you.

I was thinking that we can get around this single column key limitation
by adding a incrementing int column with a unique index to the table.
I havn't tried it, but it makes sense that it would work.

Brian

6

David,

First of all, your Rails framework is well done and has revamped my
interest in Ruby, which has been a very good thing. Thank you.

I was thinking that we can get around this single column key limitation
by adding a incrementing int column with a unique index to the table.
I havn't tried it, but it makes sense that it would work.

Brian