我想使用rake的rake db:structure:dump命令导出远程数据库结构，但每次运行该命令时，它都会忽略database.yml文件中的用户，并使用我登录为本地用户的用户。
database.yml：
development: &DEFAULT
adapter: postgresql
host: remoteaddress.com
port: 5432
user: myusername
password: mypassword
database: mydatabase
当我运行这个命令时发生了什么：
[~/src/myapp]$ RAILS_ENV=development rbbe rake db:structure:dump --trace ✭ git:em-redshift ruby:2.2.0
** Invoke db:structure:dump (first_time)
** Invoke environment (first_time)
** Execute environment
** Invoke db:load_config (first_time)
** Execute db:load_config
** Execute db:structure:dump
pg_dump: [archiver (db)] connection to database "mydatabase" failed: FATAL: password authentication failed for user "emai"
FATAL: password authentication failed for user "emai"
rake aborted!
Error dumping database
/opt/rubies/2.2.0/lib/ruby/gems/2.2.0/gems/activerecord-4.2.0/lib/active_record/tasks/postgresql_database_tasks.rb:55:in `structure_dump'
/opt/rubies/2.2.0/lib/ruby/gems/2.2.0/gems/activerecord-4.2.0/lib/active_record/tasks/database_tasks.rb:182:in `structure_dump'
/opt/rubies/2.2.0/lib/ruby/gems/2.2.0/gems/activerecord-4.2.0/lib/active_record/railties/databases.rake:276:in `block (3 levels) in <top (required)>'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/task.rb:240:in `call'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/task.rb:240:in `block in execute'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/task.rb:235:in `each'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/task.rb:235:in `execute'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/task.rb:179:in `block in invoke_with_call_chain'
/opt/rubies/2.2.0/lib/ruby/2.2.0/monitor.rb:211:in `mon_synchronize'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/task.rb:172:in `invoke_with_call_chain'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/task.rb:165:in `invoke'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:150:in `invoke_task'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:106:in `block (2 levels) in top_level'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:106:in `each'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:106:in `block in top_level'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:115:in `run_with_threads'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:100:in `top_level'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:78:in `block in run'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:176:in `standard_exception_handling'
/opt/rubies/2.2.0/lib/ruby/2.2.0/rake/application.rb:75:in `run'
/opt/boxen/rbenv/versions/2.2.0/bin/rake:33:in `<main>'
Tasks: TOP => db:structure:dump
正如你所看到的，它并没有使用myusername作为用户。相反，它将其作为我的本地用户（emai）运行。发生了什么事？
P.S. 我知道db配置也可以工作，因为我进入了rails控制台并查询记录并得到了结果。而且rake db：schema：dump可以正常工作，没有身份验证错误。