Add protected pending build column and migrate data

Changelog: performance

db/migrate/20210610102410_add_protected_attribute_to_pending_builds.rb

+# frozen_string_literal: true
+
+class AddProtectedAttributeToPendingBuilds < ActiveRecord::Migration[6.1]
+  def change
+    add_column :ci_pending_builds, :protected, :boolean, null: false, default: false
+  end
+end

db/post_migrate/20210610102413_migrate_protected_attribute_to_pending_builds.rb

+# frozen_string_literal: true
+
+class MigrateProtectedAttributeToPendingBuilds < ActiveRecord::Migration[6.1]
+  include ::Gitlab::Database::DynamicModelHelpers
+
+  disable_ddl_transaction!
+
+  def up
+    each_batch_range('ci_pending_builds', of: 1000) do |min, max|
+      execute <<~SQL
+        UPDATE ci_pending_builds
+          SET protected = true
+        FROM ci_builds
+          WHERE ci_pending_builds.build_id = ci_builds.id
+            AND ci_builds.protected = true
+            AND ci_pending_builds.id BETWEEN #{min} AND #{max}
+      SQL
+    end
+  end
+
+  def down
+    # no op
+  end
+end

db/schema_migrations/20210610102410

+dab13c78f6f758c63be923277c0f31e4cce4e30f77a8dc2983a9bb1500a454f9
\ No newline at end of file

db/schema_migrations/20210610102413

+ce21070d44a34081c6babd14e6a1b607bad5ed9047b18f4ef0beb64b5a2ce120
\ No newline at end of file

db/structure.sql

@@ -10838,7 +10838,8 @@ CREATE TABLE ci_pending_builds (
     id bigint NOT NULL,
     build_id bigint NOT NULL,
     project_id bigint NOT NULL,
-    created_at timestamp with time zone DEFAULT now() NOT NULL
+    created_at timestamp with time zone DEFAULT now() NOT NULL,
+    protected boolean DEFAULT false NOT NULL
 );
 
 CREATE SEQUENCE ci_pending_builds_id_seq

spec/migrations/migrate_protected_attribute_to_pending_builds_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+require Rails.root.join('db', 'post_migrate', '20210610102413_migrate_protected_attribute_to_pending_builds.rb')
+
+RSpec.describe MigrateProtectedAttributeToPendingBuilds do
+  let(:namespaces) { table(:namespaces) }
+  let(:projects) { table(:projects) }
+  let(:queue) { table(:ci_pending_builds) }
+  let(:builds) { table(:ci_builds) }
+
+  before do
+    namespaces.create!(id: 123, name: 'sample', path: 'sample')
+    projects.create!(id: 123, name: 'sample', path: 'sample', namespace_id: 123)
+
+    builds.create!(id: 1, project_id: 123, status: 'pending', protected: false, type: 'Ci::Build')
+    builds.create!(id: 2, project_id: 123, status: 'pending', protected: true, type: 'Ci::Build')
+    builds.create!(id: 3, project_id: 123, status: 'pending', protected: false, type: 'Ci::Build')
+    builds.create!(id: 4, project_id: 123, status: 'pending', protected: true, type: 'Ci::Bridge')
+    builds.create!(id: 5, project_id: 123, status: 'success', protected: true, type: 'Ci::Build')
+
+    queue.create!(id: 1, project_id: 123, build_id: 1)
+    queue.create!(id: 2, project_id: 123, build_id: 2)
+    queue.create!(id: 3, project_id: 123, build_id: 3)
+  end
+
+  it 'updates entries that should be protected' do
+    migrate!
+
+    expect(queue.where(protected: true).count).to eq 1
+    expect(queue.find_by(protected: true).id).to eq 2
+  end
+end