您应该将主机与端口号分开。您可能会有一些东西,例如:
development: adapter: mysql2 encoding: utf8 database: my_db_name username: root password: my_password host: 127.0.0.1 port: 3306

您应该将主机与端口号分开。您可能会有一些东西,例如:
development: adapter: mysql2 encoding: utf8 database: my_db_name username: root password: my_password host: 127.0.0.1 port: 3306