Question

在使用分页和命名范围时，我遇到了问题。使用named_scope的第二页或任何连续的分页页面仍返回第一页的结果。使用find（：all）可以正确返回分页结果。有没有人能够正确使用它们或遇到同样的问题？

class Study < ActiveRecord::Base
  named_scope :opened, :conditions => {:study_stat => [205, 11203]}
end

#find(:all) returns correct studies for both pages
Study.find(:all, :conditions => {:study_stat => [205, 11203]}).paginate(:per_page => 10,  :page => 1).each {|e| pp e.study_number  }
Study.find(:all, :conditions => {:study_stat => [205, 11203]}).paginate(:per_page => 10,  :page => 2).each {|e| pp e.study_number  }

#using named_scope returns correct result for the first page but the second page has the same studies as ones in the page one.
Study.opened.paginate(:per_page => 10,  :page => 1).each {|e| pp e.study_number  }
Study.opened.paginate(:per_page => 10,  :page => 2).each {|e| pp e.study_number  }

Answer 1

我发现了原因。如rdoc中所述，：order参数是使分页正常工作所必需的。对于named_scope尤其如此。（我使用SQL Server 2005）

User.active.paginate(:all, :per_page => 5,  :page => 1, :order=>'id').each {|e| pp e.user_name  }

User.active.paginate(:all, :per_page => 5,  :page => 2, :order=>'id').each {|e| pp e.user_name  }

Answer 2

尝试在对named_scope的paginate调用中包含：all选项。我记得前一段时间遇到过类似的问题，并为我解决了这个问题。

所以，而不是

Study.opened.paginate(:per_page => 10, :page => 2)

试

Study.opened.paginate(:all, :per_page => 10, :page => 2)

将will_paginate与named_scoped一起使用

2 个答案: