It occurs to me as a missing feature that there''s no way to indicate a
lookup
table relationship (as opposed to other sorts of foreign key relationships)
in Rails and that the scaffolding generator could recognise this lookup and
render a drop-down list automagically for the lookup table.
Say you have an Address and a State, and the State is a lookup table. In
addresses you have state_id which points to one of the entries in states. In
your models you represent this with the odd-sounding foreign key relationship
calls:
class Address #...
belongs_to :state
And the even less meaningful:
class State #...
has_many :addresses
Obviously, the scaffolding cannot take any such relationship and produce a
lookup dropdown, because it wouldn''t make sense in anything other than
these
sort of lookup table scenarios. So, perhaps there''s room for some
alternative calls that the scaffolding generator could understand (and that
would make more sense to write):
class Address #...
includes_a :state
class State #...
is_part_of :addresses
I''m pretty new to RoR, so I wanted to fly this past the minds on this
list
before thinking about it too much more. Perhaps I''ve got a solution to
a
non-problem that I only think is a problem through my own ignorance. Or is
this a worthwhile avenue to put some more effort into? What are your
thoughts?
--
Achieving life is not the equivalent of avoiding death. -- Ayn Rand
This is probably something that we all thought when first getting into RoR (which for me, wasn''t that long ago), but adding that sort of thing yourself isn''t difficult at all. Scaffolding is something rather cool that rails can do, but when it comes to real world applications, scaffolding alone doesn''t even nearly get the job done. Most people either don''t use scaffolding at all, or only use it to do the most basic parts of their project. What I''m trying to say is, you can put it off all you like, but sooner or later, you''re going to have to start learning to program in ruby. As for your suggestion of includes_a and is_part_of, I can''t see it becoming a core rails feature, but building a plugin like that might be an interesting project for someone. -Nathan On 19/05/06, Jason King <jgk@silentcow.com> wrote:> It occurs to me as a missing feature that there''s no way to indicate a lookup > table relationship (as opposed to other sorts of foreign key relationships) > in Rails and that the scaffolding generator could recognise this lookup and > render a drop-down list automagically for the lookup table. > > Say you have an Address and a State, and the State is a lookup table. In > addresses you have state_id which points to one of the entries in states. In > your models you represent this with the odd-sounding foreign key relationship > calls: > > class Address #... > belongs_to :state > > And the even less meaningful: > > class State #... > has_many :addresses > > Obviously, the scaffolding cannot take any such relationship and produce a > lookup dropdown, because it wouldn''t make sense in anything other than these > sort of lookup table scenarios. So, perhaps there''s room for some > alternative calls that the scaffolding generator could understand (and that > would make more sense to write): > > class Address #... > includes_a :state > > class State #... > is_part_of :addresses > > I''m pretty new to RoR, so I wanted to fly this past the minds on this list > before thinking about it too much more. Perhaps I''ve got a solution to a > non-problem that I only think is a problem through my own ignorance. Or is > this a worthwhile avenue to put some more effort into? What are your > thoughts? > > -- > Achieving life is not the equivalent of avoiding death. -- Ayn Rand > _______________________________________________ > Rails mailing list > Rails@lists.rubyonrails.org > http://lists.rubyonrails.org/mailman/listinfo/rails >
On 5/18/06, Jason King <jgk@silentcow.com> wrote:> I''m pretty new to RoR, so I wanted to fly this past the minds on this list > before thinking about it too much more. Perhaps I''ve got a solution to a > non-problem that I only think is a problem through my own ignorance. Or is > this a worthwhile avenue to put some more effort into? What are your > thoughts?Try the Scaffolding Extensions Plugin: http://wiki.rubyonrails.com/rails/pages/Scaffolding+Extensions+Plugin
You should also look at the ajax_scaffold_generator project: http://www.ajaxscaffold.com It allows you to customize the scaffold to do lookup tables as well. On 5/22/06, Jeremy Evans <jeremyevans0@gmail.com> wrote:> > On 5/18/06, Jason King <jgk@silentcow.com> wrote: > > I''m pretty new to RoR, so I wanted to fly this past the minds on this > list > > before thinking about it too much more. Perhaps I''ve got a solution to > a > > non-problem that I only think is a problem through my own ignorance. Or > is > > this a worthwhile avenue to put some more effort into? What are your > > thoughts? > > Try the Scaffolding Extensions Plugin: > http://wiki.rubyonrails.com/rails/pages/Scaffolding+Extensions+Plugin > _______________________________________________ > Rails mailing list > Rails@lists.rubyonrails.org > http://lists.rubyonrails.org/mailman/listinfo/rails >-------------- next part -------------- An HTML attachment was scrubbed... URL: http://wrath.rubyonrails.org/pipermail/rails/attachments/20060522/f84938b2/attachment.html
Exactly. The point of the scaffolds isn''t to write an app for you or design forms for you; hardly anyone really uses the scaffold-generated forms in any recognizabke form beyond the first half hour of a model''s life. Scaffolding is less about generating code that does something than it is about relieving the tedium and niggling errors that would result if developers had to create all of the dozens to hundreds of initial, bare files that make up a Rails app by hand and stick them in all the right places. Also bear in mind that scaffolds get generated *before* you have a chance to establish relationships in the model as you propose. All the scaffold generator has to go on is foreign key ID fields and maybe a peek at the schema, and there''s no way to tell whether widget_id is going to be pointing to a table that contains 20 widgets that would make for a nice select pulldown, or 20,000 widgets stocked in a supermarket, which may well crash a browser if fed into a select field. unknown wrote:> This is probably something that we all thought when first getting into > RoR (which for me, wasn''t that long ago), but adding that sort of > thing yourself isn''t difficult at all. Scaffolding is something rather > cool that rails can do, but when it comes to real world applications, > scaffolding alone doesn''t even nearly get the job done. Most people > either don''t use scaffolding at all, or only use it to do the most > basic parts of their project. What I''m trying to say is, you can put > it off all you like, but sooner or later, you''re going to have to > start learning to program in ruby. > > As for your suggestion of includes_a and is_part_of, I can''t see it > becoming a core rails feature, but building a plugin like that might > be an interesting project for someone. > > -Nathan-- Posted via http://www.ruby-forum.com/.