Comments on Andrew Beacock's Blog: How to rollback Rails database migrations

Cheers for your updated code, this migration rollb...

2010-03-29T20:42:55.306+01:00

Cheers for your updated code, this migration rollback code is not intended for the date-based versioning (this wasn't available at the time of the original post).

I don't work with Rails anymore so thank you for the correction! :)

I had problems with the code. The current_version...

2010-03-29T20:35:21.266+01:00

I had problems with the code. The current_version.to_i - 1 took the current version and just did a minus one. so 20100329180520 became 20100329180519 which is not what is desired. I've made some changes to the code that use the rollback method instead.

namespace :db do
namespace :migrate do
desc "Rollback the database schema to the previous version"
task :rollback => :environment do
ActiveRecord::Migrator.rollback("db/migrate/")
previous_version= ActiveRecord::Migrator.current_version.to_i
puts "Schema rolled back to previous verison (#{previous_version})."
end
end
end

Puneet, again thanks for the info! I've not p...

2009-10-21T09:22:57.764+01:00

Puneet, again thanks for the info! I've not played with Rails for nearly two years now (I changed jobs) so it's good to get advice on how it's changed since I wrote these posts back in 2007.

Also, it should be pointed out that this only work...

2009-10-21T09:18:54.434+01:00

Also, it should be pointed out that this only works with the sequential migration numbering which I suppose, was used in older rails versions.

If your rails version use timestamp based naming of migrations, you can add the following to your environment.rb to force usage of sequential migration numbers.

config.active_record.timestamped_migrations = false

Cheers Puneet, I'll update it now!

2009-10-21T09:12:05.525+01:00

Cheers Puneet, I'll update it now!

Thanks for this tip. Just a minor point, you are m...

2009-10-20T20:19:13.976+01:00

Thanks for this tip.
Just a minor point, you are missing an "end" towards the end of your script.

rake db:migrate:down VERSION=20090326173033 might ...

2009-08-23T03:42:33.579+01:00

rake db:migrate:down VERSION=20090326173033
might help

Paul, you can also just use "2" as your version nu...

2008-01-28T12:49:00.000Z

Paul, you can also just use "2" as your version number as Rails equates "002" as "2" internally anyway.

Glad you found my post some use though! :)

Useful info. I managed to rollback using "rake db...

2008-01-27T23:29:00.000Z

Useful info. I managed to rollback using "rake db:migrate VERSION=002" where the current version was named "003_add_test_data.rb" and the previous version named "002_add_price.rb". Thanks for the help.

I tried a :
"rake db:migrate VERSION=X" to see ...

2008-01-20T14:01:00.000Z

I tried a :
"rake db:migrate VERSION=X" to see what it did ..."

It removed all my my database tables

DON'T DO IT !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1

Behold, for I am become a cow, the mo-oer of world...

2007-12-13T11:12:00.000Z

Behold, for I am become a cow, the mo-oer of worlds.

Comments on Andrew Beacock's Blog: How to rollback Rails database migrations

Cheers for your updated code, this migration rollb...

I had problems with the code. The current_version...

Puneet, again thanks for the info! I've not p...

Also, it should be pointed out that this only work...

Cheers Puneet, I'll update it now!

Thanks for this tip. Just a minor point, you are m...

rake db:migrate:down VERSION=20090326173033 might ...

Paul, you can also just use "2" as your version nu...

Useful info. I managed to rollback using "rake db...

I tried a :"rake db:migrate VERSION=X" to see ...

Behold, for I am become a cow, the mo-oer of world...

I tried a :
"rake db:migrate VERSION=X" to see ...