Establishing MySQL Connectivity in Ruby on Rails 3 with Socket Connection

In managing database connections within a Ruby on Rails 3 environment on macOS, users may encounter the following error when attempting to execute migrations: "Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)." This error indicates a failure to establish a connection with the MySQL server via the specified socket file.

To resolve this issue, follow the steps below:

1. Locate the Socket File: Begin by identifying the socket file path using the following command:

   mysqladmin variables | grep socket

2. Update Database Configuration: Once you have ascertained the socket file location, modify your config/database.yml file to include the socket path under the development environment configuration:

   development:
     adapter: mysql2
     host: localhost
     username: root
     password: xxxx
     database: xxxx
     socket: /path/to/your/socket/file

Ensure that the socket file path is accurate and that the user specified in the username field possesses adequate permissions to access the MySQL server.

By implementing these steps, you will establish a stable socket connection between your Ruby on Rails 3 application and the MySQL server, thereby resolving the database connectivity issue during migrations.