How to update production database schema safely in rails 3.1.3?

问题

We need constantly update our database schema in production for rails 3.1.3 app. The first db schema was created with the following rails command:

$rake RAILS_ENV=production db:schema:load

Question is: can we still use the command above to update db schema in production while safely retaining all current data?

Thanks so much.

回答1:

I never used rake db:schema:load in production, but according to this answer to another question here on SO, I don't think you want to do that.

On the other hand, I have used RAILS_ENV=production rake db:migrate several times on the server with data already in the database and never experienced any problems.

来源：https://stackoverflow.com/questions/10131049/how-to-update-production-database-schema-safely-in-rails-3-1-3