无法连接到“127.0.0.1”上的 MySQL 服务器
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/8830091/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Can't connect to MySQL server on '127.0.0.1'
提问by Matthew Berman
I am trying to clone a repo and run it on my local machine. I don't have a DB created and I am trying to manually create my database.yml file (my first time doing this). I am not quite sure what i'm doing and keep getting errors about connecting to the MySql server. Here's my database.yml file:
我正在尝试克隆一个 repo 并在我的本地机器上运行它。我没有创建数据库，我正在尝试手动创建我的 database.yml 文件（我第一次这样做）。我不太确定我在做什么，并且不断收到有关连接到 MySql 服务器的错误。这是我的 database.yml 文件：
development:
adapter: mysql
host: 127.0.0.1
database: db/app_development
username: root
password:
I also tried localhost instead of 127.0.0.1, both give me errors when trying to create the db by doing 'bundle exec rake db:create' ...i get this error:
我还尝试了 localhost 而不是 127.0.0.1，在尝试通过执行 'bundle exec rake db:create' 创建数据库时，两者都给我错误...我收到此错误：
Can't connect to MySQL server on '127.0.0.1' (61)
Couldn't create database for {"username"=>"root", "adapter"=>"mysql", "database"=>"db/app_development", "host"=>"127.0.0.1", "password"=>nil}, charset: utf8, collation: utf8_unicode_ci
I know i'm doing something wrong but I can't quite figure out what it is. Do I need to start the mysql server or something?
我知道我做错了什么，但我无法弄清楚它是什么。我需要启动mysql服务器还是什么？
This is the output when I run mysqld_safe:
这是我运行 mysqld_safe 时的输出：
120111 20:35:39 mysqld_safe Logging to '/usr/local/var/mysql/Matthew-Bermans-MacBook-Air.local.err'.
120111 20:35:39 mysqld_safe Starting mysqld daemon with databases from /usr/local/var/mysql
120111 20:35:41 mysqld_safe mysqld from pid file /usr/local/var/mysql/Matthew-Bermans-MacBook-Air.local.pid ended
采纳答案by Michael Durrant
Try:
尝试：
development:
adapter: mysql
database: app_development
username: root
password:
socket: /var/lib/mysql/mysql.sock
Then do your rake db:createto create it from rails.
or
in mysql do create database db_name
and then the above code for :developmentwill let you use it.
然后做你的rake db:create从导轨创建它。
或者
在mysql中做create database db_name
然后上面的代码:development会让你使用它。
Update:Matthew first needs to get mySQL installed on his (Mac) machine.
I directed him to http://dev.mysql.com/downloads/mysql/
更新：Matthew 首先需要在他的 (Mac) 机器上安装 mySQL。
我引导他到http://dev.mysql.com/downloads/mysql/
回答by VivekVarade123
Explicitly mention your port: 3306in your database.yml
port: 3306在 database.yml 中明确提及您
If that doesn't work then executed
如果这不起作用，则执行
netstat -tupln
and check if MySQL is listening to port 3306or not
并检查如果MySQL侦听端口3306或不
回答by Michael Maltese
If you don't mind what database software you use (I don't think you specified whether you needed MySQL or just wanted to get the repo to work), you might try using SQLite3 instead. SQLite3 doesn't run a server or use ports, so it might be easier for you to get setup.
如果你不介意你使用什么数据库软件（我认为你没有指定是需要 MySQL 还是只是想让 repo 工作），你可以尝试使用 SQLite3。SQLite3 不运行服务器或使用端口，因此您可能更容易进行设置。
Try imitating the rails default database.yml, which looks like:
尝试模仿 rails 默认的 database.yml，它看起来像：
# SQLite version 3.x
# gem install sqlite3
#
# Ensure the SQLite 3 gem is defined in your Gemfile
# gem 'sqlite3'
development:
adapter: sqlite3
database: db/development.sqlite3
pool: 5
timeout: 5000
Then add gem 'sqlite3'to your Gemfile and run bundle install
然后添加gem 'sqlite3'到您的 Gemfile 并运行bundle install
Hope this helps!
希望这可以帮助！
回答by Hussain Akram
It can also be solved by changing MySQL version. Had the same issue with some project which was developed using MySQL 5.5but installed version in my mac was MySQL 5.7 so I had to downgrade my version and it worked for me.
也可以通过更改 MySQL 版本来解决。一些使用MySQL 5.5开发的项目也有同样的问题，但在我的 mac 中安装的版本是 MySQL 5.7，所以我不得不降级我的版本，它对我有用。
回答by alexs333
First of all, try executing the following to check if you have a connection to mysql from command prompt (without Ruby on Rails).
首先，尝试执行以下命令以检查您是否从命令提示符（没有 Ruby on Rails）连接到 mysql。
mysql -u root
If cannot connect you probably specified and password. You will need to either remember it or reinstall MySQL. If you can, then create your database:
如果无法连接，您可能指定了密码。您需要记住它或重新安装 MySQL。如果可以，请创建您的数据库：
create database app_development;
Last but no the least, remove prefix 'db/' from database.yml. You don't need a full path:
最后但同样重要的是，从 database.yml 中删除前缀“db/”。您不需要完整路径：
database: app_development
Hope that helps!
希望有帮助！
