Add indices to abuse_reports table

Add indices on user_id and reporter_id to abuse_reports table.
Also fix the use of include for /admin/abuse_reports page
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/controllers/admin/abuse_reports_controller.rb

@@ -4,7 +4,7 @@ class Admin::AbuseReportsController < Admin::ApplicationController
   # rubocop: disable CodeReuse/ActiveRecord
   def index
     @abuse_reports = AbuseReport.order(id: :desc).page(params[:page])
-    @abuse_reports.includes(:reporter, :user)
+    @abuse_reports = @abuse_reports.includes(:user, :reporter)
   end
   # rubocop: enable CodeReuse/ActiveRecord
 

changelogs/unreleased/dz-add-indices-to-abuse-reports.yml

+---
+title: Improve performance of admin/abuse_reports page
+merge_request: 19630
+author:
+type: performance

db/post_migrate/20191105140942_add_indices_to_abuse_reports.rb

+# frozen_string_literal: true
+
+class AddIndicesToAbuseReports < ActiveRecord::Migration[5.2]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :abuse_reports, :user_id
+  end
+
+  def down
+    remove_concurrent_index :abuse_reports, :user_id
+  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: 2019_11_05_094625) do
+ActiveRecord::Schema.define(version: 2019_11_05_140942) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_trgm"
@@ -24,6 +24,7 @@ ActiveRecord::Schema.define(version: 2019_11_05_094625) do
     t.datetime "updated_at"
     t.text "message_html"
     t.integer "cached_markdown_version"
+    t.index ["user_id"], name: "index_abuse_reports_on_user_id"
   end
 
   create_table "alerts_service_data", force: :cascade do |t|