Will_paginate mangles object ids if named

false

2009-02-23T11:10:22-08:00

25969

250 will_paginate-mangles-object-ids-if-named_scope-includes-a-join 101

466

new will_paginate Will_paginate mangles object ids if named_scope includes a :join

2009-02-23T11:16:23-08:00

25969

Adam Florin

Chris Wanstrath

http://err.lighthouseapp.com/projects/466/tickets/250

It looks like if you use will_paginate in conjunction with an ActiveRecord named_scope with a :join, will_paginate will jam the ids of the joined table in place of the actual ids of the returned objects. Kinda hard to explain; it's a weird bug. I'll pull an example from our source. Take two models, Review and Story, where Review belongs_to :story. If I set up a simple named scope like: @@@ class Review < ActiveRecord::Base named_scope :visible, :conditions => {:status => 'visible'} end @@@ and then do: @@@ Review.visible.paginate(:page => 1) @@@ All the returned reviews are OK. However, if I just add a join to that named_scope (perfectly legal) like: @@@ class Review < ActiveRecord::Base named_scope :visible, :conditions => {'reviews.status' => ['list', 'feature']}, :joins => "JOIN stories ON reviews.story_id=stories.id" end @@@ ...and then run the same paginate call as above, my results look like: @@@ [#<Review id: 182, story_id: 182>, #<Review id: 183, story_id: 183>, ...] @@@ Where the story_ids are all correct and the Review ids are all incorrectly set to match the story ids. This has to do with how will_paginate or something is parsing the SQL results (which are correct). Note that if I feed an explicit :select to paginate like :select => "reviews.id, reviews.story_id", then the ids _are_ correct.

<div>It looks like if you use will_paginate in conjunction with an ActiveRecord named_scope with a :join, will_paginate will jam the ids of the joined table in place of the actual ids of the returned objects. Kinda hard to explain; it's a weird bug. I'll pull an example from our source. Take two models, Review and Story, where Review belongs_to :story. If I set up a simple named scope like: <pre><code> class Review < ActiveRecord::Base named_scope :visible, :conditions => {:status => 'visible'} end </code></pre> and then do: <pre><code> Review.visible.paginate(:page => 1) </code></pre> All the returned reviews are OK. However, if I just add a join to that named_scope (perfectly legal) like: <pre><code> class Review < ActiveRecord::Base named_scope :visible, :conditions => {'reviews.status' => ['list', 'feature']}, :joins => "JOIN stories ON reviews.story_id=stories.id" end </code></pre> ...and then run the same paginate call as above, my results look like: <pre><code> [#<Review id: 182, story_id: 182>, #<Review id: 183, story_id: 183>, ...] </code></pre> Where the story_ids are all correct and the Review ids are all incorrectly set to match the story ids. This has to do with how will_paginate or something is parsing the SQL results (which are correct). Note that if I feed an explicit :select to paginate like :select => "reviews.id, reviews.story_id", then the ids are correct.</div>