Heroku耙db：migrate不起作用

Question

im having this issue when i try to deploy my ruby on rails application to heroku, i check different posts here, because i saw this issue before but i couldnt fix it. when i try to run:

$ heroku rake db:migrate

I get a lot of these ones: DEPRECATION WARNING :

and then:

rake aborted!
Please install the postgresql adapter: `gem install activerecord-postgresql-adapter` (pg is not part of the bundle. Add it to Gemfile.)

Tasks: TOP => db:migrate => db:load_config
(See full trace by running task with --trace)

I tried to change my Gemfile with 'pg' and my group :assets do to :production, i know im missing something but i could'nt figured out what.

Some ideas?

Also when I go to the app url, I get this:

Application Error
An error occurred in the application and your page could not be served. Please try again in a few moments.
If you are the application owner, check your logs for details.

Thanks in advance for any suggest and help!!!

Answer 1

You have to use Postgres on Heroku, you can't use sqlite3 because Heroku prohibits you from saving to the file system. So add the pg gem to your production bundle and re-deploy then your migrations should run.

Answer 2

Answer here is simple, add the following production in your gemfile as:

group :production do
  gem 'pg'
end

Your local machine won't work with this production, so we now have to bundle it by ignoring PostgreSQL gem which can be done as:

bundle install --without production

After this, try heroku rake db:migrate . Must work.

Good luck