Rebuilding dependent views

[HakubJozak]

On my current project, we have a following layered structure of table and 2 views:

A) ledger_breakdown_keys - table
B) ledger_billing_entries - view built on top of A
C) ledger_usage_entries - materialized view on top of B

When I need to update the underlying table A, I often have to rebuild B and C but I haven't found an out-of-the-box way of how to rebuild a dependent materialized view in Scenic. So far I am using this migration (see example).

Do you think that abstracting that could be in any way useful to others? Dependent views does not seem to be so uncommin usecase but I may be wrong. I can forge a PR if we agree that would be useful:

 class AddMovieDcuIdToLedger < ActiveRecord::Migration[7.0]
  def up
    rebuild_billing_views_after(4, 3) do
      add_column :ledger_breakdown_keys, :movie_dcu_id, :bigint
    end
  end

  def down
    rebuild_billing_views_after(3, 2) do
      remove_column :ledger_breakdown_keys, :movie_dcu_id, :bigint
    end
  end

  private

  def rebuild_billing_views_after(billing_view_version, usage_view_version)
    raise 'Missing block' unless block_given?

    execute "DROP MATERIALIZED VIEW IF EXISTS ledger_usage_entries CASCADE"
    execute "DROP VIEW IF EXISTS ledger_billing_entries CASCADE"

    yield

    execute "CREATE VIEW ledger_billing_entries AS #{definition('ledger_billing_entries', billing_view_version)}"
    execute "CREATE MATERIALIZED VIEW ledger_usage_entries AS #{definition('ledger_usage_entries', usage_view_version)}"
  end

  def definition(name, version)
    Scenic::Definition.new(name, version).to_sql.rstrip.chomp(';')
  end
end