Ok, been banging my head on this and just can''t figure it. Normally, any table that has a belongs_to to another table you can easily access it by: table1.table2.field And it works perfectly for one table I have. Let''s call it... tags. So, I''ve got: Tag -> has_many :blah_tags Blah -> has_many :blah_tags Blah_tag -> belongs_to :tag, belongs_to :blah Ok, works fine. Based on a blah_tag entry, I can go blah_tag.blah.name (or whatever). No problem. Substitute, an identical setup for say Colour, and bam. The whole thing throws nils everywhere. I may have a big batch of valid colour_tags, but try to go: colour_tag.colour => NIL! I don''t get it. Identical table setups....identical code.... is colour reserved? Do I need to restart servers or something (tried that...)? Am I going crazy? It makes no sense to me. Thanks! mm -- Posted via http://www.ruby-forum.com/.
Am Freitag, den 24.03.2006, 03:08 +0100 schrieb meltman:> Ok, been banging my head on this and just can''t figure it. Normally, any > table that has a belongs_to to another table you can easily access it > by: > > table1.table2.field > > And it works perfectly for one table I have. Let''s call it... tags. So, > I''ve got: > > Tag -> has_many :blah_tags > Blah -> has_many :blah_tags > Blah_tag -> belongs_to :tag, belongs_to :blah > > Ok, works fine. Based on a blah_tag entry, I can go blah_tag.blah.name > (or whatever). No problem. > > Substitute, an identical setup for say Colour, and bam. The whole thing > throws nils everywhere. I may have a big batch of valid colour_tags, but > try to go: colour_tag.colour => NIL! > > I don''t get it. Identical table setups....identical code.... is colour > reserved? Do I need to restart servers or something (tried that...)? Am > I going crazy? > > It makes no sense to me.Please show us some concrete code. -- Norman Timmler http://blog.inlet-media.de
Well I don''t have it in front of me at the moment, but there''s
nothing
crazy going on:
class Colour < ActiveRecord::Base
has_many :entry_colours
end
class Entry < ActiveRecord::Base
has_many :entry_colours
end
class EntryColour < ActiveRecord::Base
belongs_to :colour
belongs_to :entry
end
class Search < ApplicationController
def search
@colour = Colour.find(:first, :conditions => [ "name=Red" ])
@results = EntryColour.find(:all,:conditions
=>["colour_id=?",@colour.id])
#this bit is actually embedded in HTML but we''ll put it here...
@results.each |result| do
result.entry.name
end
end
end
I don''t know if there''s just something out of whack.... or
what. I tried
flushing the temp files, restarting everything... no dice. But another
table with literally the identical setup works fine. Does it hate the
word colour?
The things in @results are valid.
mm
Norman Timmler wrote:> Am Freitag, den 24.03.2006, 03:08 +0100 schrieb meltman:
>> Blah -> has_many :blah_tags
>> reserved? Do I need to restart servers or something (tried that...)? Am
>> I going crazy?
>>
>> It makes no sense to me.
>
> Please show us some concrete code.
>
> --
> Norman Timmler
>
> http://blog.inlet-media.de
--
Posted via http://www.ruby-forum.com/.
meltman wrote:> Well I don''t have it in front of me at the moment, but there''s nothing > crazy going on: > > class Colour < ActiveRecord::Base > has_many :entry_colours > end > > class Entry < ActiveRecord::Base > has_many :entry_colours > end > > class EntryColour < ActiveRecord::Base > belongs_to :colour > belongs_to :entry > endYou seem to be querying a slightly odd way. If Colour has_many EntryColours, you should be able to say @colour.entry_colours.each{ |ec| ...} Can you ? Another thing to try is use script/console to load a Colour and inspect it. Silly Question, perhaps, but is there a reason you''re specifically avoiding has_and_belongs_to_many ? Then you could do @colour = Colour.find(:first, :conditions => [ "name=Red" ]) @colour.entries.each{|entry| entry.name} or @entry.colours.each{|colour| colour.name} Can you post the schema for those three tables ? It may be down to foreign key placement and/or whether the join table has it''s own id? A. -- Posted via http://www.ruby-forum.com/.
Alan Francis wrote:> You seem to be querying a slightly odd way. If Colour has_many > EntryColours, you should be able to say @colour.entry_colours.each{ |ec| > ...} Can you ?Indeed I probably can (code not in front of me right now), or at least I should be. I''m relatively new to this whole Rails thing, and that certainly would be a much easier way to do the query.> Silly Question, perhaps, but is there a reason you''re specifically > avoiding has_and_belongs_to_many ?Hahaha, no, and I probably should be using it since the queries are certainly easier. Like I said, pretty new to the whole Rails thing, and really, to relational DBs in general. (I''m a recent perl convert whose been living in flat-file hell for too long!) So I appreciate the patience for my obviously moronic inquiries. Ok, so the schema (also not in front of me is pretty basic): table: colours id (int, auto-inc, primary key) name (varchar) table: entries id (int, auto-inc, primary key) name (varchar) table: entry_colours colour_id (int, primary key) entry_id (int, primary key) That''s it... it''s really just something I''m fooling around with to get my bearings in the new environment. What has me really mystified is that I had it working with another ''join'' table or whatever, and then when I tried adding this second one, it didn''t work. So I''m a bit mystified. Thanks again. mm -- Posted via http://www.ruby-forum.com/.
meltman wrote:> Alan Francis wrote: >> You seem to be querying a slightly odd way. If Colour has_many >> EntryColours, you should be able to say @colour.entry_colours.each{ |ec| >> ...} Can you ? > > Indeed I probably can (code not in front of me right now), or at least I > should be. I''m relatively new to this whole Rails thing, and that > certainly would be a much easier way to do the query. > >> Silly Question, perhaps, but is there a reason you''re specifically >> avoiding has_and_belongs_to_many ? > > Hahaha, no, and I probably should be using it since the queries are > certainly easier. Like I said, pretty new to the whole Rails thing, andAha! :-) Then life''s about to get easier. So, here goes... table: colours (id, name) table: entries (id, name) table: colours_entries (colour_id, entry_id) note its important the the two names in the join table be in alpha order for rails automagic to work...entries_colours won''t work. model: Colour, has_and_belongs_to_many :entries model: Entry, has_and_belongs_to_many :colours You can now do: red = Colour.find(1) red.entries.each{ |entry| entry.do_something } or entry = Entry.find(1} entry.colours.each{ |colour| colour.do_something } You can go from entry to color back to entry again.. entry.colours.each{ |colour| colour.entries.name } For more info, see http://www.slash7.com/cheats/activerecord_cheatsheet.pdf Alan -- Posted via http://www.ruby-forum.com/.
Alan Francis wrote:> Aha! :-) Then life''s about to get easier.Indeed it has!> note its important the the two names in the join table be in alpha order > for rails automagic to work...entries_colours won''t work.Oh my god! Alpha order! Man, is that documented somewhere?!> model: Colour, has_and_belongs_to_many :entries > model: Entry, has_and_belongs_to_many :coloursOh man, so much easier, so you don''t even *need* the intermediate model anymore.... I swear, every day Rails gets better and better. Thanks so much for the help! mm -- Posted via http://www.ruby-forum.com/.
meltman wrote:> Alan Francis wrote: >> Aha! :-) Then life''s about to get easier. > > Indeed it has! > >> note its important the the two names in the join table be in alpha order >> for rails automagic to work...entries_colours won''t work. > > Oh my god! Alpha order! Man, is that documented somewhere?! >Indeed it is! http://rails.rubyonrails.com/classes/ActiveRecord/Associations/ClassMethods.html -- Posted via http://www.ruby-forum.com/.