Add partial index for ci_builds on project_id and status

changelogs/unreleased/53994-add-missing-ci_builds-partial-indices.yml

+---
+title: Add partial index for ci_builds on project_id and status
+merge_request: 23268
+author:
+type: performance

db/migrate/20181121101842_add_ci_builds_partial_index_on_project_id_and_status.rb

+# frozen_string_literal: true
+
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddCiBuildsPartialIndexOnProjectIdAndStatus < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index(*index_arguments)
+  end
+
+  def down
+    remove_concurrent_index(*index_arguments)
+  end
+
+  private
+
+  def index_arguments
+    [
+      :ci_builds,
+      [:project_id, :status],
+      {
+        name: 'index_ci_builds_project_id_and_status_for_live_jobs_partial2',
+        where: "(((type)::text = 'Ci::Build'::text) AND ((status)::text = ANY (ARRAY[('running'::character varying)::text, ('pending'::character varying)::text, ('created'::character varying)::text])))"
+      }
+    ]
+  end
+end

db/schema.rb

@@ -352,6 +352,7 @@ ActiveRecord::Schema.define(version: 20181126153547) do
     t.index ["commit_id", "type", "ref"], name: "index_ci_builds_on_commit_id_and_type_and_ref", using: :btree
     t.index ["id"], name: "partial_index_ci_builds_on_id_with_legacy_artifacts", where: "(artifacts_file <> ''::text)", using: :btree
     t.index ["project_id", "id"], name: "index_ci_builds_on_project_id_and_id", using: :btree
+    t.index ["project_id", "status"], name: "index_ci_builds_project_id_and_status_for_live_jobs_partial2", where: "(((type)::text = 'Ci::Build'::text) AND ((status)::text = ANY (ARRAY[('running'::character varying)::text, ('pending'::character varying)::text, ('created'::character varying)::text])))", using: :btree
     t.index ["protected"], name: "index_ci_builds_on_protected", using: :btree
     t.index ["runner_id"], name: "index_ci_builds_on_runner_id", using: :btree
     t.index ["scheduled_at"], name: "partial_index_ci_builds_on_scheduled_at_with_scheduled_jobs", where: "((scheduled_at IS NOT NULL) AND ((type)::text = 'Ci::Build'::text) AND ((status)::text = 'scheduled'::text))", using: :btree