how to specify the database in the config? - ruby-on-rails

Question

please help solve the problem.
I made a website. I use sqlite3.
database.yml:
default: &default
adapter: sqlite3
pool: 5
timeout: 5000
development:
<<: *default
database: db/development.sqlite3
test:
<<: *default
database: db/test.sqlite3
production:
<<: *default
database: db/production.sqlite3
gemfile:
source 'https://rubygems.org'
gem 'rails', '4.2.1'
gem 'sass-rails', '~> 5.0'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.1.0'
gem 'jquery-rails'
gem 'turbolinks'
gem 'jbuilder', '~> 2.0'
gem 'sdoc', '~> 0.4.0', group: :doc
gem 'bootstrap-sass', '3.2.0.0'
gem 'bcrypt', '~> 3.1.7'
gem 'populate'
gem 'faker'
gem 'russian', '~> 0.6.0'
gem 'will_paginate'
gem 'paperclip'
gem 'fancybox2-rails', '~> 0.2.8'
gem 'rspec-rails'
gem 'factory_girl'
gem 'database_cleaner'
group :development do
gem 'sqlite3'
end
group :production do
gem 'pg'
gem 'rails_12factor'
end
group :development, :test do
gem 'byebug'
gem 'web-console', '~> 2.0'
gem 'spring'
end
on the local server it is running. I uploaded it to heroku. as a result of getting the following error message:
500 internal server error
heroku uses postgresql. that's the problem. please help set up configuration

Answer 1

It is as it says: You need to add pg gem. Include the following line in your Gemfile
gem 'pg', group: :production
And you in your config/database.yml file, you can write the following code with appropriate modifications:
development:
adapter: postgresql
encoding: unicode
database: myapp_development
pool: 5
username: myapp
password: password1
test:
adapter: postgresql
encoding: unicode
database: myapp_test
pool: 5
username: myapp
password: password1
production:
adapter: postgresql
encoding: unicode
database: myapp_prouduction
pool: 5
username: myapp
password: password1