Postgree too many connections in rails console - ruby-on-rails

Question

I am developing a Ruby on Rails app using postgre gem and this is how my database.yml looks like:
development:
adapter: postgresql
encoding: utf-8
pool: 5
username: "hytxlzju"
password: "xxxxx"
host: "jumbo.db.elephantsql.com"
port: "5432"
database: "hytxlzju"
production:
adapter: postgresql
encoding: utf-8
pool: 5
username: "hytxlzju"
password: "xxxxxx"
host: "jumbo.db.elephantsql.com"
port: "5432"
database: "hytxlzju"
Whenever I am connecting to this db locally, from the rails console I am getting too many connections. How can I kill a connection in the code, once the user logged out, in the code, and how can I kill one in my rails console, after I finished altering the tables?
[EDIT]
This is the error message:
C:/RailsInstaller/Ruby2.2.0/lib/ruby/gems/2.2.0/gems/activerecord-3.2.22.5/lib/active_record/connection_adapters/postgresql_adapter.rb:12
22:in `initialize': FATAL: too many connections for role "hytxlzju" (PG::ConnectionBad)
[EDIT] I added my initilizer, still no success:
Rails.application.config.after_initialize do
ActiveRecord::Base.connection_pool.disconnect!
ActiveSupport.on_load(:active_record) do
config = ActiveRecord::Base.configurations[Rails.env] ||
Rails.application.config.database_configuration[Rails.env]
config['pool'] = ENV['DB_POOL'] || ENV['RAILS_MAX_THREADS'] || 5
ActiveRecord::Base.establish_connection(config)
end
end

Answer 1

You can try the below approach
Active Record limits the total number of connections per application
through a database setting pool; this is the maximum size of the
connections your app can have to the database
in config/datbase.yml
pool: <%= ENV['RAILS_MAX_THREADS'] || 5 %>
If you are using puma then use ENV['RAILS_MAX_THREADS'] more here
It might solve the problem.

Answer 2

[SOLVED]
Somehow my demo app was not finding the entries in the tables, so it was creating multiple pools connections, without closing them, because before closing the connection, a 500 error was getting thrown, hence that bit of code where I closed the pool was never closed. More abut postgre session here
https://devcenter.heroku.com/articles/concurrency-and-database-connections#connection-pool