Rails migrations are not reversible RB-LI1107
Anti-pattern
Major
ActiveRecord migrations should be reversible, by implementing either a change method, or both an up and a down method.
Bad practice
class SomeMigration < ActiveRecord::Migration[6.0]
def up
# up migration
end
# <----- missing down method
end
class SomeMigration < ActiveRecord::Migration[6.0]
# <----- missing up method
def down
# down migration
end
end
Recommended
class SomeMigration < ActiveRecord::Migration[6.0]
def change
# reversible migration
end
end
class SomeMigration < ActiveRecord::Migration[6.0]
def up
# up migration
end
def down
# down migration
end
end