我在Ubuntu 11.10和RubyMine上运行我的开发
这是我对database.yml的开发设置：RubyMine为我创建的
development:
adapter: postgresql
encoding: unicode
database: mydb_development
pool: 5
username: myuser
password:
当我尝试运行应用程序时，我在下面收到此错误，似乎我还没有创建“项目”用户，但是，我如何创建用户并在postgres中为其授予数据库？如果这是问题，那么，在Ubuntu中为此任务使用的推荐工具是什么？如果这不是问题，请咨询。
Exiting
/home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/postgresql_adapter.rb:1194:in `initialize': FATAL: Peer authentication failed for user "project" (PG::Error)
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/postgresql_adapter.rb:1194:in `new'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/postgresql_adapter.rb:1194:in `connect'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/postgresql_adapter.rb:329:in `initialize'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/postgresql_adapter.rb:28:in `new'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/postgresql_adapter.rb:28:in `postgresql_connection'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:303:in `new_connection'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:313:in `checkout_new_connection'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:237:in `block (2 levels) in checkout'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:232:in `loop'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:232:in `block in checkout'
from /home/sam/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:229:in `checkout'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:95:in `connection'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:398:in `retrieve_connection'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_specification.rb:168:in `retrieve_connection'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/connection_adapters/abstract/connection_specification.rb:142:in `connection'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/model_schema.rb:308:in `clear_cache!'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activerecord-3.2.3/lib/active_record/railtie.rb:91:in `block (2 levels) in <class:Railtie>'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activesupport-3.2.3/lib/active_support/callbacks.rb:418:in `_run__757346023__prepare__404863399__callbacks'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activesupport-3.2.3/lib/active_support/callbacks.rb:405:in `__run_callback'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activesupport-3.2.3/lib/active_support/callbacks.rb:385:in `_run_prepare_callbacks'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activesupport-3.2.3/lib/active_support/callbacks.rb:81:in `run_callbacks'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/actionpack-3.2.3/lib/action_dispatch/middleware/reloader.rb:74:in `prepare!'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/actionpack-3.2.3/lib/action_dispatch/middleware/reloader.rb:48:in `prepare!'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/application/finisher.rb:47:in `block in <module:Finisher>'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/initializable.rb:30:in `instance_exec'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/initializable.rb:30:in `run'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/initializable.rb:55:in `block in run_initializers'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/initializable.rb:54:in `each'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/initializable.rb:54:in `run_initializers'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/application.rb:136:in `initialize!'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/railtie/configurable.rb:30:in `method_missing'
from /home/sam/RubymineProjects/project/config/environment.rb:5:in `<top (required)>'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `require'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `block in require'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:236:in `load_dependency'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/activesupport-3.2.3/lib/active_support/dependencies.rb:251:in `require'
from /home/sam/RubymineProjects/project/config.ru:4:in `block in <main>'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/rack-1.4.1/lib/rack/builder.rb:51:in `instance_eval'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/rack-1.4.1/lib/rack/builder.rb:51:in `initialize'
from /home/sam/RubymineProjects/project/config.ru:1:in `new'
from /home/sam/RubymineProjects/project/config.ru:1:in `<main>'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/rack-1.4.1/lib/rack/builder.rb:40:in `eval'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/rack-1.4.1/lib/rack/builder.rb:40:in `parse_file'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/rack-1.4.1/lib/rack/server.rb:200:in `app'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/commands/server.rb:46:in `app'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/rack-1.4.1/lib/rack/server.rb:301:in `wrapped_app'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/rack-1.4.1/lib/rack/server.rb:252:in `start'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/commands/server.rb:70:in `start'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/commands.rb:55:in `block in <top (required)>'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/commands.rb:50:in `tap'
from /home/sam/.rvm/gems/ruby-1.9.3-p0@project/gems/railties-3.2.3/lib/rails/commands.rb:50:in `<top (required)>'
from /home/sam/RubymineProjects/project/script/rails:6:in `require'
from /home/sam/RubymineProjects/project/script/rails:6:in `<top (required)>'
from -e:1:in `load'
from -e:1:in `<main>'
Process finished with exit code 1
答案 0 :(得分：292)
如果您在服务器上安装了postresql，那么只需托管：localhost到database.yml，我通常会把它放在它所说的pool周围：5。否则如果不是localhost肯定告诉应用程序在哪里找到它的数据库。
development:
adapter: postgresql
encoding: unicode
database: kickrstack_development
host: localhost
pool: 5
username: kickrstack
password: secret
通过创建数据库并为应用的用户分配所有权以建立连接，确保正确设置了用户凭据。要在postgresql 9中创建新用户，请运行：
sudo -u postgres psql
如果你没有设置postgresql用户密码，它只是反斜杠密码。
postgres=# \password
创建新用户和密码以及用户的新数据库：
postgres=# create user "guy_on_stackoverflow" with password 'keepitonthedl';
postgres=# create database "dcaclab_development" owner "guy_on_stackoverflow";
现在，在确认创建数据库，用户，密码并设置这些权限后，请更新database.yml文件。不要忘记host：localhost。
答案 1 :(得分：52)
这是让你的rails应用程序在Ubuntu 13.10中的 开发环境 中使用postgres最简单的方法。
1）在Gemfile中使用postgres YAML和'pg'gem创建rails应用程序：
$ rails new my_application -d postgresql
2）给它一些CRUD功能。如果您只是看到postgres是否有效，请创建一个脚手架：
$ rails g scaffold cats name:string age:integer colour:string
3）从rails 4.0.1开始，-d postgresql选项生成不包含主机参数的YAML。 我发现我需要这个。编辑开发部分并创建以下参数：
encoding: UTF-8
host: localhost
database: my_application_development
username: thisismynewusername
password: thisismynewpassword
请注意，database参数适用于尚未退出的数据库，username和password是不存在的角色的凭据。我们稍后会创建它们！
这就是config/database.yml看起来的样子（在复制品中没有羞耻感：D）：
development:
adapter: postgresql
pool: 5
# these are our new parameters
encoding: UTF-8
database: my_application_development
host: localhost
username: thisismynewusername
password: thisismynewpassword
test:
# this won't work
adapter: postgresql
encoding: unicode
database: my_application_test
pool: 5
username: my_application
password:
production:
# this won't work
adapter: postgresql
encoding: unicode
database: my_application_production
pool: 5
username: my_application
password:
4）使用以下命令启动postgres shell：
$ psql
4a）如果您当前的用户（如在您的计算机用户中）没有相应的管理postgres角色，则可能会收到此错误。
psql: FATAL: role "your_username" does not exist
现在我只安装了一次postgres，所以我可能在这里错了，但我认为postgres会自动创建一个管理角色，其凭据与您安装postgres的用户具有相同的凭据。
4b）所以这意味着你需要更改为安装postgres的用户使用psql命令并启动shell：
$ sudo su postgres
然后运行
$ psql
5）你会知道你在postgres shell中，因为你的终端会是这样的：
$ psql
psql (9.1.10)
Type "help" for help.
postgres=#
6）使用postgresql语法，让我们创建我们在{{1>}的开发部分中指定的用户：
config/database.yml现在，这里有一些细微之处，让我们来看看它们。
你应该在终端上看到这个：
postgres=# CREATE ROLE thisismynewusername WITH LOGIN PASSWORD 'thisismynewpassword';
这意味着，“ROLE CREATED”，但postgres'警报似乎采用了与git hub相同的命令式约定。
7）现在，仍然在postgres shell中，我们需要使用我们在YAML中设置的名称创建数据库。让我们在步骤6中创建的用户成为其所有者：
postgres=#
CREATE ROLE
postgres=#
你会知道你是否成功，因为你会得到输出：
postgres=# CREATE DATABASE my_application_development OWNER thisismynewusername;
8）退出postgres shell：
CREATE DATABASE
9）现在是真相：
\q
如果你得到这个：
$ RAILS_ENV=development rake db:migrate
恭喜，postgres与您的应用完美配合。
9a）在我的本地计算机上，我一直收到权限错误。我不记得确切，但这是一个错误的
== CreateCats: migrating =================================================
-- create_table(:cats)
-> 0.0028s
== CreateCats: migrated (0.0028s) ========================================
虽然我建议仔细考虑在本地生成机器上递归设置写入权限，但我给了我整个应用程序读写权限，如下所示：
9b）爬上一个目录级别：
Can't access the files. Change permissions to 666.
9c）将my_application目录及其所有内容的权限设置为666：
$ cd ..
9d）再次运行迁移：
$ chmod -R 0666 my_application
如果你搞砸了一些提示和技巧
在重新启动所有这些步骤之前尝试这些：
mynewusername用户没有CRUD到$ RAILS_ENV=development rake db:migrate
== CreateCats: migrating =================================================
-- create_table(:cats)
-> 0.0028s
== CreateCats: migrated (0.0028s) ========================================
数据库的权限？删除数据库并使用mynewusername作为所有者再次创建它：
1）启动postgres shell：
my_app_development 2）删除$ psql
数据库。小心！ Drop意味着彻底删除！
my_app_development 3）重新创建另一个postgres=# DROP DATABASE my_app_development;
并将mynewusername设为所有者：
my_app_development4）退出shell：
postgres=# CREATE DATABASE my_application_development OWNER mynewusername;
postgres=# \q
用户无法登录数据库？认为您在YAML中写了错误的密码，并且不记得您使用postgres shell输入的密码？只需使用YAML密码更改角色：
1）打开你的YAML，并将密码复制到剪贴板：
mynewusername2）启动postgres shell：
development:
adapter: postgresql
pool: 5
# these are our new parameters
encoding: UTF-8
database: my_application_development
host: localhost
username: thisismynewusername
password: musthavebeenverydrunkwheniwrotethis
3）更新$ psql
的密码。粘贴密码，并记住在其周围加上单引号：
mynewusername4）退出shell：
postgres=# ALTER ROLE mynewusername PASSWORD `musthavebeenverydrunkwheniwrotethis`;
尝试通过数据库查看器（如Dbeaver）连接到localhost，并且不知道你的postgres用户的密码是什么？改变如下：
1）以超级用户身份运行postgres=# \q
：
passwd 2）输入$ sudo passwd postgres
的帐户密码（与postgres无关）：
sudo3）创建postgres帐户的新密码：
[sudo] password for starkers: myaccountpassword
收到此错误消息？：
Enter new UNIX password: databasesarefun
Retype new UNIX password: databasesarefun
passwd: password updated successfully
4）您需要为您的用户提供创建数据库的能力。来自psql shell：
Run `$ bin/rake db:create db:migrate` to create your database
$ rake db:create db:migrate
PG::InsufficientPrivilege: ERROR: permission denied to create database
答案 2 :(得分：29)
永久解决方案：
问题在于你的pg_hba。这一行：
local all postgres peer
应该是
local all postgres md5
然后在更改此文件后重新启动postgresql服务器。
如果您使用的是Linux，则命令为
sudo service postgresql restart
答案 3 :(得分：9)
我在Ubuntu机器上遇到同样的问题，所以我按照一些步骤删除了这个错误。 切换到postgres用户
$ sudo su - postgres
它将要求输入密码，默认密码为postgres
将用户切换到postgres后，打开psql console
$ psql
如果有多个版本可用，请检查postgres的版本
psql=# select VERSION();
PostgreSQL 9.1.13 on x86_64-unk.... # so version is 9.1
现在打开postgres user
vim /etc/postgresql/9.1/main/pg_hba.conf
9.1是版本返回表单上层命令
并替换
local all postgres peer
到
local all postgres md5
sudo service postgresql restart
我也在我的博客上写了一些步骤
http://tarungarg402.blogspot.in/2014/10/set-up-postgresql-on-ubuntu.html
答案 4 :(得分：5)
您可以转到/var/lib/pgsql/data/pg_hba.conf文件并添加信任来代替Ident 它对我有用。
local all all trust
host all 127.0.0.1/32 trust
有关详细信息，请参阅此问题 Ident authentication failed for user
答案 5 :(得分：1)
添加“ host：locahost”是我的魔力
development:
adapter: postgresql
database: database_name_here
host: localhost
username: user_name_here
答案 6 :(得分：0)
如果在运行单元测试时收到该错误消息（Peer authentication failed for user (PG::Error)），请确保测试数据库存在。
答案 7 :(得分：0)
在开发环境中工作时，我也遇到了同样的问题，问题是我在host: localhost文件中留下了config/database.yml的注释。
因此我的应用程序无法连接到PostgreSQL数据库，只需取消注释即可解决该问题。
development:
<<: *default
database: database_name
username: database_username
password: database_password
host: localhost
仅此而已。
我希望这会有所帮助