在rails上迁移DB时遇到问题

Question

我试图为我的兄弟在铁轨上创建一个在线商店，当我尝试迁移我的数据库时，会弹出这个错误

rails db:migrate
rails aborted!
ActiveRecord::NoDatabaseError: FATAL:  role "manuel" does not exist
/home/manuel/Shopper/bin/rails:9:in `require'
/home/manuel/Shopper/bin/rails:9:in `<top (required)>'
/home/manuel/Shopper/bin/spring:15:in `<top (required)>'
bin/rails:3:in `load'
bin/rails:3:in `<main>'

引起：

PG::ConnectionBad: FATAL:  role "manuel" does not exist
/home/manuel/Shopper/bin/rails:9:in `require'
/home/manuel/Shopper/bin/rails:9:in `<top (required)>'
/home/manuel/Shopper/bin/spring:15:in `<top (required)>'
bin/rails:3:in `load'
bin/rails:3:in `<main>'
Tasks: TOP => db:migrate