#strong_migrations error - ValidatePlanAndAccountNotNull & CreatePayV3Models

=== Dangerous operation detected #strong_migrations ===

Setting NOT NULL on an existing column blocks reads and writes while every row is checked.
Instead, add a check constraint and validate it in a separate migration.

class ValidatePlanAndAccountNotNull < ActiveRecord::Migration[6.1]
  def change
    add_check_constraint :plans, "name IS NOT NULL", name: "plans_name_null", validate: false
  end
end

class ValidateValidatePlanAndAccountNotNull < ActiveRecord::Migration[6.1]
  def change
    validate_check_constraint :plans, name: "plans_name_null"
  end
end

/jumpstart/db/migrate/20210115211740_validate_plan_and_account_not_null.rb:8:in `change'

=== Dangerous operation detected #strong_migrations ===

Adding a column with a non-null default blocks reads and writes while the entire table is rewritten.
Instead, add the column without a default value, then change the default.

class CreatePayV3Models < ActiveRecord::Migration[6.1]
  def up
    add_column :plans, :interval_count, :integer
    change_column_default :plans, :interval_count, 1
  end

  def down
    remove_column :plans, :interval_count
  end
end

Then backfill the existing rows in the Rails console or a separate migration with disable_ddl_transaction!.

class BackfillCreatePayV3Models < ActiveRecord::Migration[6.1]
  disable_ddl_transaction!

  def up
    Plan.unscoped.in_batches do |relation| 
      relation.update_all interval_count: 1
      sleep(0.01)
    end
  end
end

/jumpstart/db/migrate/20210804000959_create_pay_v3_models.rb:4:in `change'