Add index to optimize usage data counters

- needed for failing counters on .com due
  to long queries

changelogs/unreleased/208887-optimize-project-counters-mirrored-pipelines.yml

+---
+title: Optimize Project counters with pipelines enabled counter
+merge_request: 26802
+author:
+type: performance

db/migrate/20200309195209_add_index_on_project_id_and_builds_access_level_to_project_features.rb

+# frozen_string_literal: true
+
+class AddIndexOnProjectIdAndBuildsAccessLevelToProjectFeatures < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+  INDEX_NAME = 'index_project_features_on_project_id_bal_20'
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :project_features, :project_id, where: 'builds_access_level = 20', name: INDEX_NAME
+  end
+
+  def down
+    remove_concurrent_index_by_name :project_features, INDEX_NAME
+  end
+end

db/migrate/20200309195710_add_index_on_mirror_and_creator_id_and_created_at_to_projects.rb

+# frozen_string_literal: true
+
+class AddIndexOnMirrorAndCreatorIdAndCreatedAtToProjects < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+  INDEX_NAME = 'index_projects_on_mirror_creator_id_created_at'
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :projects, [:creator_id, :created_at], where: 'mirror = true and mirror_trigger_builds = true', name: INDEX_NAME
+  end
+
+  def down
+    remove_concurrent_index_by_name :projects, INDEX_NAME
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2020_03_06_170531) do
+ActiveRecord::Schema.define(version: 2020_03_09_195710) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_trgm"
@@ -3264,6 +3264,7 @@ ActiveRecord::Schema.define(version: 2020_03_06_170531) do
     t.integer "pages_access_level", null: false
     t.integer "forking_access_level"
     t.index ["project_id"], name: "index_project_features_on_project_id", unique: true
+    t.index ["project_id"], name: "index_project_features_on_project_id_bal_20", where: "(builds_access_level = 20)"
   end
 
   create_table "project_group_links", id: :serial, force: :cascade do |t|
@@ -3465,6 +3466,7 @@ ActiveRecord::Schema.define(version: 2020_03_06_170531) do
     t.index ["created_at", "id"], name: "index_projects_api_created_at_id_desc", order: { id: :desc }
     t.index ["created_at", "id"], name: "index_projects_api_vis20_created_at", where: "(visibility_level = 20)"
     t.index ["created_at", "id"], name: "index_projects_on_created_at_and_id"
+    t.index ["creator_id", "created_at"], name: "index_projects_on_mirror_creator_id_created_at", where: "((mirror = true) AND (mirror_trigger_builds = true))"
     t.index ["creator_id"], name: "index_projects_on_creator_id"
     t.index ["description"], name: "index_projects_on_description_trigram", opclass: :gin_trgm_ops, using: :gin
     t.index ["id", "repository_storage", "last_repository_updated_at"], name: "idx_projects_on_repository_storage_last_repository_updated_at"