If two people go to the same rails application (same directory) and both run "rake db:migrate" to update the database with a set of migrations (the same ones) at the same time, is it likely that bad things will happen to the data, or will db:migrate do something to prevent the same migration from being run by more than one (simultaneous) process?
Thanks, --Paul
If two people go to the same rails application (same directory) and both run "rake db:migrate" to update the database with a set of migrations (the same ones) at the same time, is it likely that bad things will happen to the data, or will db:migrate do something to prevent the same migration from being run by more than one (simultaneous) process?
rake db:migrate is only tuned for one development workstation.
Are you implying your developers don't have individual databases?
In my experience running various rake commands accidentally at the same time, one batch will "win", and the other will cough up a zillion errors and expire gracelessly...
Depending on your DB, it may support transactional migrations (as of Rails 2.2). That should ensure that only one set of changes go through. Haven't ever tried it, but it should probably work.
--Matt Jones