Add index on pipelines to project id and source

db/migrate/20180916011959_add_index_pipelines_project_id_source.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 AddIndexPipelinesProjectIdSource < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :ci_pipelines, [:project_id, :source]
+  end
+
+  def down
+    remove_concurrent_index :ci_pipelines, [:project_id, :source]
+  end
+end

db/schema.rb

@@ -475,6 +475,7 @@ ActiveRecord::Schema.define(version: 20180917172041) do
   add_index "ci_pipelines", ["project_id", "iid"], name: "index_ci_pipelines_on_project_id_and_iid", unique: true, where: "(iid IS NOT NULL)", using: :btree
   add_index "ci_pipelines", ["project_id", "ref", "status", "id"], name: "index_ci_pipelines_on_project_id_and_ref_and_status_and_id", using: :btree
   add_index "ci_pipelines", ["project_id", "sha"], name: "index_ci_pipelines_on_project_id_and_sha", using: :btree
+  add_index "ci_pipelines", ["project_id", "source"], name: "index_ci_pipelines_on_project_id_and_source", using: :btree
   add_index "ci_pipelines", ["project_id", "status", "config_source"], name: "index_ci_pipelines_on_project_id_and_status_and_config_source", using: :btree
   add_index "ci_pipelines", ["project_id"], name: "index_ci_pipelines_on_project_id", using: :btree
   add_index "ci_pipelines", ["status"], name: "index_ci_pipelines_on_status", using: :btree