Schema Migrations Table

Question

In my Rails 4 app I would like to collapse my migration files into one large file (similar to schema.rb) as it's time to do some housekeeping but I'm not sure on how to access the table in the database that stores migration data so that when I run a migration I don't receive any errors/conflicts.

Question How can I access and delete the data in the table that stores migration data?

Answer 1

for fun, you can also manipulate these in the console by making a model class for them...

class SchemaMigration < ActiveRecord::Base; self.primary_key = :version; end 

then you can do SchemaMigration.all, SchemaMigration.last.delete, etc.

Really just a substitute for using SQL, and it is very rare that you would need to mess around at this low level… generally a bad idea but cool to see how to do it :)

Answer 2

Another solution could be to access it through:

ActiveRecord::SchemaMigration

The answer given by David didn't work in my context.

Answer 3

The schema_migrations table holds the revision numbers; with the last record being the most recently executed migration. You can just manipulate these records manually.