Optimize projects with repositories enabled

Adds an index as well as start/finish times to optimize the counter

changelogs/unreleased/213799-optimize-usage_activity_by_stage-projects_with_repositories_enable.yml

+---
+title: Optimize projects with repositories enabled usage data
+merge_request: 29117
+author:
+type: performance

db/migrate/20200408153842_add_index_on_creator_id_and_id_on_projects.rb

+# frozen_string_literal: true
+
+class AddIndexOnCreatorIdAndIdOnProjects < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :projects, [:creator_id, :id]
+  end
+
+  def down
+    remove_concurrent_index :projects, [:creator_id, :id]
+  end
+end

db/structure.sql

@@ -9918,6 +9918,8 @@ CREATE INDEX index_projects_on_creator_id_and_created_at ON public.projects USIN
 
 CREATE INDEX index_projects_on_creator_id_and_created_at_and_id ON public.projects USING btree (creator_id, created_at, id);
 
+CREATE INDEX index_projects_on_creator_id_and_id ON public.projects USING btree (creator_id, id);
+
 CREATE INDEX index_projects_on_description_trigram ON public.projects USING gin (description public.gin_trgm_ops);
 
 CREATE INDEX index_projects_on_id_and_archived_and_pending_delete ON public.projects USING btree (id) WHERE ((archived = false) AND (pending_delete = false));
@@ -13131,6 +13133,7 @@ COPY "schema_migrations" (version) FROM STDIN;
 20200407094005
 20200407094923
 20200408110856
+20200408153842
 20200408175424
 \.
 

ee/lib/ee/gitlab/usage_data.rb

@@ -234,7 +234,10 @@ module EE
             merge_requests_with_optional_codeowners: distinct_count(::ApprovalMergeRequestRule.code_owner_approval_optional.where(time_period), :merge_request_id),
             merge_requests_with_required_codeowners: distinct_count(::ApprovalMergeRequestRule.code_owner_approval_required.where(time_period), :merge_request_id),
             projects_imported_from_github: distinct_count(::Project.github_imported.where(time_period), :creator_id),
-            projects_with_repositories_enabled: distinct_count(::Project.with_repositories_enabled.where(time_period), :creator_id),
+            projects_with_repositories_enabled: distinct_count(::Project.with_repositories_enabled.where(time_period),
+                                                               :creator_id,
+                                                               start: ::User.minimum(:id),
+                                                               finish: ::User.maximum(:id)),
             protected_branches: distinct_count(::Project.with_protected_branches.where(time_period), :creator_id, start: ::User.minimum(:id), finish: ::User.maximum(:id)),
             remote_mirrors: distinct_count(::Project.with_remote_mirrors.where(time_period), :creator_id),
             snippets: distinct_count(::Snippet.where(time_period), :author_id),