Being someone who likes to write code and do everything myself this rails deal has me grinding my teeth, but I will get over it. I just noticed after doing a "rake db:migrate" that I mispelled a method/column name. So before doing anything else, I corrected the spelling in the relevant db/migrate .rb file and ran "rake db:migrate" again hoping that would do. However, looking in the db/schema.rb file, nothing had changed. So I erased that and the database and tried rake again and hopefully everything is fine BUT that is hackish, to say the least. I've only glanced through the rake docs, --help, etc, and can't find anything pertinent to the issue. Anyone nice wanna explain quick? The other part of my question: does rake affect anything outside db/ ? If not, everything should be hunky dory. Right?
on 2009-05-20 23:04
on 2009-05-20 23:13
On May 20, 10:04 pm, Mk 27 <rails-mailing-l...@andreas-s.net> wrote: > rake db:rollback rolls back the last migration you've run > I've only glanced through the rake docs, --help, etc, and can't find > anything pertinent to the issue. Anyone nice wanna explain quick? rake is a fairly generic ruby tool, so the rake documentation is unlikely to be helpful. in a given context (eg inside your rails folder) rake -T will list available tasks. The migrations guide ( http://guides.rubyonrails.org/migrations.html#runn... ) has some more info. > > The other part of my question: does rake affect anything outside db/ ? rake tasks are arbitrary ruby code. in theory you could have a rake task that launched a missile at the moon. The tasks that rails provides in the db: namespace do just fiddle with the database (or related files like schema.rb) Fred
on 2009-05-20 23:13
If a rake db:migrate succeeds but you realise it is not what you want then the thing to do is 'rake db:rollback' which will run the 'down' part of the previous migration and so should take you back to where you were. Then correct the migration and run it again. If a migration fails, however, you must manually undo any changes made before the error, correct the code and migrate again. Do not do a rollback in this case as it will go back to the one before you started, if you understand me. At least this is the case on MySQL which does not handle transactions which include changes to db structure. I am not sure whether the situation is different with other db types. Colin 2009/5/20 Mk 27 <email@example.com>
on 2009-05-21 00:28
Frederick Cheung wrote: > rake tasks are arbitrary ruby code. in theory you could have a rake > task that launched a missile at the moon. The tasks that rails > provides in the db: namespace do just fiddle with the database (or > related files like schema.rb) > > Fred Thanks all!
on 2009-05-21 02:11
Surprised nobody mentioned: rake db:migrate:redo VERSION=<xxx> It lets you redo a single migration, don't forget to dump the table and then reload it if you want to keep the data. Brendon.