我正在我的rails项目中将我的数据库从sqlite3转换为PostgreSQL，所以我遵循本教程：https://devcenter.heroku.com/articles/sqlite3
我完成了所有必要的更改，但最后我想要发出命令：
rake db:create
rake db:migrate
我有这些错误：
FATAL: role "ubuntu" does not exist
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:825:in `initialize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:825:in `new'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:825:in `connect'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:542:in `initialize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:41:in `new'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:41:in `postgresql_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:440:in `new_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:450:in `checkout_new_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:421:in `acquire_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:356:in `block in checkout'
/home/ubuntu/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/monitor.rb:211:in `mon_synchronize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:355:in `checkout'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:265:in `block in connection'
/home/ubuntu/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/monitor.rb:211:in `mon_synchronize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:264:in `connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:546:in `retrieve_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_handling.rb:79:in `retrieve_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_handling.rb:53:in `connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/postgresql_database_tasks.rb:8:in `connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/postgresql_database_tasks.rb:17:in `create'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:72:in `create'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:86:in `block in create_current'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:182:in `block in each_current_configuration'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:181:in `each'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:181:in `each_current_configuration'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:85:in `create_current'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/railties/databases.rake:20:in `block (2 levels) in <top (required)>'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:236:in `call'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:236:in `block in execute'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:231:in `each'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:231:in `execute'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:175:in `block in invoke_with_call_chain'
/home/ubuntu/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/monitor.rb:211:in `mon_synchronize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:168:in `invoke_with_call_chain'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:161:in `invoke'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:149:in `invoke_task'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:106:in `block (2 levels) in top_level'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:106:in `each'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:106:in `block in top_level'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:115:in `run_with_threads'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:100:in `top_level'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:78:in `block in run'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:165:in `standard_exception_handling'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:75:in `run'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/bin/rake:33:in `<top (required)>'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/bin/rake:23:in `load'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/bin/rake:23:in `<main>'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/bin/ruby_executable_hooks:15:in `eval'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/bin/ruby_executable_hooks:15:in `<main>'
Couldn't create database for {"adapter"=>"postgresql", "database"=>"my_data_base_development", "pool"=>5, "timeout"=>5000}
FATAL: role "ubuntu" does not exist
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:825:in `initialize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:825:in `new'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:825:in `connect'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:542:in `initialize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:41:in `new'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/postgresql_adapter.rb:41:in `postgresql_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:440:in `new_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:450:in `checkout_new_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:421:in `acquire_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:356:in `block in checkout'
/home/ubuntu/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/monitor.rb:211:in `mon_synchronize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:355:in `checkout'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:265:in `block in connection'
/home/ubuntu/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/monitor.rb:211:in `mon_synchronize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:264:in `connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:546:in `retrieve_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_handling.rb:79:in `retrieve_connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/connection_handling.rb:53:in `connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/postgresql_database_tasks.rb:8:in `connection'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/postgresql_database_tasks.rb:17:in `create'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:72:in `create'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:86:in `block in create_current'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:182:in `block in each_current_configuration'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:181:in `each'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:181:in `each_current_configuration'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/tasks/database_tasks.rb:85:in `create_current'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.0/lib/active_record/railties/databases.rake:20:in `block (2 levels) in <top (required)>'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:236:in `call'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:236:in `block in execute'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:231:in `each'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:231:in `execute'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:175:in `block in invoke_with_call_chain'
/home/ubuntu/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/monitor.rb:211:in `mon_synchronize'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:168:in `invoke_with_call_chain'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/task.rb:161:in `invoke'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:149:in `invoke_task'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:106:in `block (2 levels) in top_level'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:106:in `each'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:106:in `block in top_level'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:115:in `run_with_threads'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:100:in `top_level'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:78:in `block in run'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:165:in `standard_exception_handling'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/lib/rake/application.rb:75:in `run'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/gems/rake-10.1.0/bin/rake:33:in `<top (required)>'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/bin/rake:23:in `load'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/bin/rake:23:in `<main>'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/bin/ruby_executable_hooks:15:in `eval'
/home/ubuntu/.rvm/gems/ruby-2.0.0-p247/bin/ruby_executable_hooks:15:in `<main>'
Couldn't create database for {"adapter"=>"postgresql", "database"=>"my_data_base_test", "pool"=>5, "timeout"=>5000}
这是我的代码：
photo.rb：
class Photo < ActiveRecord::Base
has_attached_file :image
end
Gemfile：
# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.0.0'
gem 'bootstrap-sass', '2.3.2'
gem "paperclip", "~> 3.0"
gem "rake"
# Use sqlite3 as the database for Active Record
gem 'pg'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.0'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .js.coffee assets and views
gem 'coffee-rails', '~> 4.0.0'
# See https://github.com/sstephenson/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby
# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
gem 'turbolinks'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 1.2'
group :doc do
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', require: false
end
# Use ActiveModel has_secure_password
# gem 'bcrypt-ruby', '~> 3.0.0'
# Use unicorn as the app server
# gem 'unicorn'
# Use Capistrano for deployment
# gem 'capistrano', group: :development
# Use debugger
# gem 'debugger', group: [:development, :test]
XXXXXXXXXXXX_create_image.rb：
class CreatePhotos < ActiveRecord::Migration
def change
create_table :photos do |t|
t.timestamps
end
end
def self.up
add_column :photos, :image_file_name, :string
add_column :photos, :image_content_type, :string
add_column :photos, :image_file_size, :string
add_column :photos, :image_update_at, :string
end
def self.down
remove_column :photos, :image_file_name, :string
remove_column :photos, :image_content_type, :string
remove_column :photos, :image_file_size, :string
remove_column :photos, :image_update_at, :string
end
end
database.yml：
# SQLite version 3.x
# gem install sqlite3
#
# Ensure the SQLite 3 gem is defined in your Gemfile
# gem 'sqlite3'
development:
adapter: postgresql
database: my_data_base_development
pool: 5
timeout: 5000
# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
adapter: postgresql
database: my_data_base_test
pool: 5
timeout: 5000
production:
adapter: postgresql
database: my_data_base_production
pool: 5
timeout: 5000
您有想法让我的迁移工作吗？谢谢
答案 0 :(得分：1)
您应该按照this guide设置Postgres和Rails：
本教程的这一部分介绍了如何为Postgres设置用户：
设置Postgres 为我们的Rails应用程序创建一个Postgres用户 在下一步中创建。为此，请切换到Postgres用户：
su - postgres然后创建一个用户（或“角色”，就像Postgres所说的那样）：
create role myapp with createdb login password 'password1'
但是，您应该使用ubuntu代替myapp来创建必要的角色。
答案 1 :(得分：0)
您的数据库没有“ubuntu”角色。这是您在database.yml文件中作为用户使用的内容。你必须创建它。在postgres中运行：
CREATE ROLE ubuntu WITH LOGIN ENCRYPTED PASSWORD 'type-your-password' CREATEDB;
然后，您可以使用ALTER ROLE更改角色权限。这样允许用户使用以下内容创建角色和数据库：
ALTER ROLE owlphabet CREATEROLE CREATEDB REPLICATION SUPERUSER;
我发现此链接非常有用。
http://blog.jasonmeridth.com/2012/10/02/postgresql-command-line-cheat-sheet.html
此外，您没有在database.yml中包含角色/用户 - 您需要让它们看起来像这样：
development:
adapter: postgresql
encoding: unicode
database: my_data_base_development
pool: 5
username: ubuntu
password: type_your_password
host: localhost
当然也要改变生产和测试。