Rails schema rb not updating updating in cold fusion
Last but not least, if you ever use the Suspenders gem to generate your base Rails application with thoughtbot’s standard defaults, you might have noticed that it adds a can be kept for data that is required in any environment.
In summary, by creating a temporary rake task, we get the benefits of more robust deployments, non-destructive migrations, and more control over the data manipulation process.
If our database is quite large, it is also recommended to run the data migration in batches.
You can read more about batches on the Rails Guides at Retrieving Multiple Objects in Batches.
The downside is that we need remember to either add this rake task to our deployment script or run the rake task manually after deployment.
We will also need to clean up after ourselves and remove the temporary rake task once the changes have been deployed and implemented.
A second issue is that those data migrations might be ignored by future developers if instead of running file without touching the migrations.
For example when moving money around, we want to guarantee that there will not be a situation where money is withdrawn from one account, but not deposited to another account. If the data change requires more actions, consider pulling out that behaviour into its own method.The first obvious option that comes to mind is to use a Rails migration, especially since the word “migration” is already in the task at hand, a “data migration.” But let’s talk about it some more and let me try to dissuade you from doing so.Looking the at Rails Guides for Active Records Migration, the first section starts by saying: Migrations are a feature of Active Record that allows you to evolve your database schema over time.Temporary rake tasks allow us to decouple a deployment from completed migrations.It gives us more control of the data manipulation process by encapsulating it in one place.