在Rails中，无法为{“adapter”=>“postgresql”创建数据库，

我正在尝试运行rake db:create或rake db:setup但是我收到以下错误。 这很奇怪，因为rake db:create使用其他Rails项目从其他文件夹中rake db:create它正常工作。

 user:project user$ rake db:create could not connect to server: No such file or directory Is the server running locally and accepting connections on Unix domain socket "/var/pgsql_socket/.s.PGSQL.5432"? /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord- 3.1.0/lib/active_record/connection_adapters/postgresql_adapter.rb:991:in `initialize' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord- 3.1.0/lib/active_record/connection_adapters/postgresql_adapter.rb:991:in `new' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/postgresql_adapter.rb:991:in `connect' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/postgresql_adapter.rb:260:in `initialize' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/postgresql_adapter.rb:27:in `new' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/postgresql_adapter.rb:27:in `postgresql_connection' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord- 3.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:304:in `new_connection' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:323:in `checkout_new_connection' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord- 3.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:265:in `block (2 levels) in checkout' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord- 3.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:261:in `loop' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:261:in `block in checkout' /Users/user/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:260:in `checkout' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:162:in `connection' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:409:in `retrieve_connection' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/abstract/connection_specification.rb:107:in `retrieve_connection' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/connection_adapters/abstract/connection_specification.rb:89:in `connection' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/railties/databases.rake:110:in `rescue in create_database' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.1.0/lib/active_record/railties/databases.rake:54:in `create_database' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/activerecord- 3.1.0/lib/active_record/railties/databases.rake:42:in `block (2 levels) in ' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `call' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `block in execute' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `each' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `execute' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/task.rb:158:in `block in invoke_with_call_chain' /Users/user/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/task.rb:144:in `invoke' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:116:in `invoke_task' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block (2 levels) in top_level' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `each' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block in top_level' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:88:in `top_level' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:66:in `block in run' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run' /Users/user/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/bin/rake:33:in `' /Users/user/.rvm/gems/ruby-1.9.2-p290/bin/rake:19:in `load' /Users/user/.rvm/gems/ruby-1.9.2-p290/bin/rake:19:in `' Couldn't create database for {"adapter"=>"postgresql", "database"=>"project_test", "username"=>nil, "password"=>nil, "min_messages"=>"warning"} 

这是我的database.yml

 development: adapter: postgresql database: project_development username: password: min_messages: warning test: adapter: postgresql database: project_test username: password: min_messages: warning production: adapter: postgresql database: project_production username: password: min_messages: warning 

Posgree托管在/usr/local/var/postgres 。 不应该rake尝试在同一个文件夹中查找它而不是/var/pgsql_socket/ ？ （反正我没有/ usr / local / var / pgsql_socket）

Answer 1

解决了！

解决方案很容易更新当前安装的gem。

另一个尝试的解决方案是设置host: localhost或您在database.yml文件上的开发设置上使用的任何主机。

Answer 2

我通过Homebrew在Mac OS X上安装了PG（我没有意识到它在Mac OS X中是默认的），并且遇到了同样的问题。 我可能通过在通过Homebrew安装pg之前安装pg gem使问题变得更糟。

我通过执行以下操作解决了同样的问题：

1. 确保所有二进制文件都指向Cellar目录中的二进制文件（Mac OS X上的/ usr / local / Cellar）
2. 卸载pg gem gem uninstall pg
3. 使用Homebrew configs重新安装gem install pg -- --with-pg-config=/usr/local/bin/pg_config （如果你使用pg setup创建了一个rails项目，这在你的database.yml配置文件中有解释）

它奏效了！

Answer 3

我遇到了一个相同的问题，并能够通过以下方式解决错误：

1. 使用postgresapp.com（由heroku在https://devcenter.heroku.com/articles/heroku-postgresql#local-setup中推荐），

2. 添加到config / database.yml

    host: localhost 

3. 按照http://postgresapp.com/documentation的问题排查部分中的建议重置共享内存设置：

    sudo sysctl -w kern.sysv.shmall=65536 sudo sysctl -w kern.sysv.shmmax=16777216 

Answer 4

上面zquintana的答案对我有一些小的警告。

我的解决方案（使用Homebrew）：

1. 如果你有gem安装gem uninstall pg
2. 删除postgresql brew uninstall postgresql旧副本
3. 重新安装postgresql brew install postgresql
4. 安装说明提到：

要在登录时启动postgresql：

ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents

然后立即加载postgresql：

launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist

或者，如果您不想/需要launchctl，您可以运行：

postgres -D /usr/local/var/postgres

4. 所以运行ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents
5. 然后launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist

6. 现在用Homebrew configs gem install pg -- --with-pg-config=/usr/local/bin/pg_config重新安装gem gem install pg -- --with-pg-config=/usr/local/bin/pg_config

7. 现在运行你的rake db:create

Answer 5

就我而言，这就是我所需要的： https ： //dba.stackexchange.com/a/75221

 pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start 

Answer 6

还要检查您是否没有打开的连接，例如客户端或连接到该实例的应用程序。 如果发生这种情况，您将在错误中看到这一点

 Couldn't create database for {"adapter"=>"xxxx", "database"=>"xxxx", "host"=>"localhost", "username"=>"postgres", "password"=>"xxxxx", "pool"=>5, "timeout"=>5000} rake aborted! ActiveRecord::StatementInvalid: PG::ObjectInUse: ERROR: source database "template1" is being accessed by other users DETAIL: There is 1 other session using the database. 

Answer 7

首先，您需要在Postgres中手动创建用户，同时为此用户授予数据库创建权限（AKA createdb）。

为此，首先打开Postgres shell提示符

$ sudo -u postgres psql

创建您的用户

postgres=# create role Your_DB_username with createdb login password 'YOUR_PASSWORD';

从Postgres shell退出

postgres=# \q

做任何与db相关的rake任务：

$ rake db:create

它会工作！

Answer 8

我能够通过确保database.yml文件中的数据库名称采用以下格式来解决这个问题：appname_development，appname_test和appname_production。 这是我的database.yml文件作为示例：

  development: adapter: postgresql database: parallax_development username: password: test: adapter: postgresql database: parallax_test username: password: production: adapter: postgresql database: parallax_production username: password: