ruby-on-rails - Heroku 推送问题第 2 部分 - Postgresql - PGError 关系不存在 - Ruby on Rails

Question

好吧，关于 Postgresql 和 SQLite 之间的区别的最后一个问题已经解决了，似乎 Heroku 告诉我我还有另一个问题。我是 ruby​​ 和 rails 的新手，所以很多东西一开始我都看不懂。在这里寻找一点方向。错误消息和 PostsController 索引如下。我检查了我的 routes.rb 文件，一切看起来都很好，但我可能遗漏了一些东西。如果你需要，我会发布。

Processing PostsController#index (for 99.7.50.140 at 2010-04-23 15:19:22) [GET]

ActiveRecord::StatementInvalid (PGError: ERROR:  relation "tags" does not exist
:             SELECT a.attname, format_type(a.atttypid, a.atttypmod), d.adsrc, a.attnotnull
              FROM pg_attribute a LEFT JOIN pg_attrdef d
                ON a.attrelid = d.adrelid AND a.attnum = d.adnum
             WHERE a.attrelid = '"tags"'::regclass
               AND a.attnum > 0 AND NOT a.attisdropped
             ORDER BY a.attnum
):

PostsController#index

  def index
    @tag_counts = Tag.count(:group => :tag_name, 
       :order => 'count_all DESC', :limit => 20)
       conditions, joins = {}, :votes

    @ugtag_counts = Ugtag.count(:group => :ugctag_name, 
       :order => 'count_all DESC', :limit => 20)
       conditions, joins = {}, :votes

    @vote_counts = Vote.count(:group => :post_title, 
          :order => 'count_all DESC', :limit => 20)
          conditions, joins = {}, :votes


       unless(params[:tag_name] || "").empty?
         conditions = ["tags.tag_name = ? ", params[:tag_name]]
         joins = [:tags, :votes]
       end
       @posts=Post.paginate(
                 :select => "posts.*, count(*) as vote_total", 
                 :joins => joins, 
                 :conditions=> conditions, 
                 :group => "votes.post_id, posts.id ", 
                 :order => "created_at DESC",
                 :page => params[:page], :per_page => 5)
        @popular_posts=Post.paginate(
                 :select => "posts.*, count(*) as vote_total", 
                 :joins => joins, 
                 :conditions=> conditions, 
                 :group => "votes.post_id, posts.id", 
                 :order => "vote_total DESC",
                 :page => params[:page], :per_page => 3)

    respond_to do |format|
      format.html # index.html.erb
      format.xml  { render :xml => @posts }
      format.json { render :json => @posts }
      format.atom
    end
  end

Answer 1

从 rails 3.0.3 升级到 rails 3.0.5 时，我遇到了类似的“PGError: ERROR: relation “...” does not exist”问题——看起来数据库名称复数算法已经改变.我以前必须复数的内容:“project_metadatas”现在称为“project_metadata”。

对我来说，解决方法是添加一个重命名有问题的表的简单迁移:

class MetadataName < ActiveRecord::Migration
  def self.up
    rename_table :project_metadatas, :project_metadata
  end

  def self.down
    rename_table :project_metadata, :project_metadatas
  end
end