具有正确的Rails命名和约定的“PG :: UndefinedTable：ERROR：relation不存在”

我已经阅读了很多像这样的底池，但我见过的所有解决方案都在模型，命名和Rails惯例的命名中。

现在，当我在PostgreSQL 9.1中的生产环境中第一次运行时， 我遇到了这个问题

rake db:migrate RAILS_ENV=production 

要么

  rake db:schema:load RAILS_ENV=production 

我可以毫无问题地创建数据库： rake db:create RAILS_ENV=production => OK

错误是

 rake aborted! PG::UndefinedTable: ERROR: relation "categories" does not exist LINE 5: WHERE a.attrelid = '"categories"'::regclass ^ : SELECT a.attname, format_type(a.atttypid, a.atttypmod), pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod FROM pg_attribute a LEFT JOIN pg_attrdef d ON a.attrelid = d.adrelid AND a.attnum = d.adnum WHERE a.attrelid = '"categories"'::regclass AND a.attnum > 0 AND NOT a.attisdropped ORDER BY a.attnum 

这些模型遵循所有Rails命名约定。 所以，我不知道这个错误告诉我什么？还有其他什么可以导致这个错误？

型号：

 class Category < ActiveRecord::Base has_many :subcategories end class Subcategory < ActiveRecord::Base belongs_to :category end 

shema.rb：

 ActiveRecord::Schema.define(version: nnnn) do # These are extensions that must be enabled in order to support this database enable_extension "plpgsql" create_table "categories", force: true do |t| t.string "name" t.text "comments" t.datetime "created_at" t.datetime "updated_at" t.decimal "amount_need_comments", precision: 6, scale: 2 t.decimal "amount", precision: 6, scale: 2 t.decimal "amount_per_unit", precision: 6, scale: 2 t.integer "teletrabajo", limit: 2, default: 0, null: false t.decimal "amount_need_city", precision: 6, scale: 2 end create_table "subcategories", force: true do |t| t.string "name" t.text "comments" t.integer "category_id" t.datetime "created_at" t.datetime "updated_at" t.decimal "amount_need_comments", precision: 6, scale: 2 t.decimal "amount", precision: 6, scale: 2 t.decimal "amount_per_unit", precision: 6, scale: 2 t.decimal "amount_need_city", precision: 6, scale: 2 end 

最后，我尝试了这样的事情，没有成功

是inflections.rb

 ActiveSupport::Inflector.inflections do |inflect| inflect.irregular 'category', 'categories' inflect.irregular 'subcategory', 'subcategories' inflect.plural 'category', 'categories' inflect.plural 'subcategory', 'subcategories' end 

并删除所涉及的模型的关系，如下所示：

 class ExpenseDetail "id" validate :expense_date... 

…

Answer 1

我有同样的问题，我发现在我的迁移中，我没有复数forms的表名：

例如：

class CreatePosts ActiveRecord::Migration def change create_table :posts do |t| t.string :source t.string :destination t.datetime :time t.timestamps end end end
class CreatePosts ActiveRecord::Migration def change create_table :posts do |t| t.string :source t.string :destination t.datetime :time t.timestamps end end end 

我有create_table :post ，但当我将其更改为create_table :posts 。 它开始工作!!!!

Answer 2

我再次遇到了自己的错误!!，在执行rake test ，但是在这种情况下感谢cedricdlb我在这里找到了解决方案，非常简单：

 rake db:test:prepare rake db:test:load