Add user_id and created_at to Version

https://gitlab.com/gitlab-org/gitlab/issues/12604
https://gitlab.com/gitlab-org/gitlab/issues/32081
https://gitlab.com/gitlab-org/gitlab/issues/13426

changelogs/unreleased/13426-add-user-and-timestamps-to-design-management-version.yml

+---
+title: Add user_id and created_at columns to design_management_versions table
+merge_request: 17316
+author:
+type: added

db/migrate/20190918025618_add_user_and_timestamps_to_design_management_versions.rb

+# frozen_string_literal: true
+
+class AddUserAndTimestampsToDesignManagementVersions < ActiveRecord::Migration[5.2]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def up
+    add_column :design_management_versions, :user_id, :integer
+    add_column :design_management_versions, :created_at, :datetime_with_timezone
+  end
+
+  def down
+    remove_columns :design_management_versions, :user_id, :created_at
+  end
+end

db/migrate/20190926041216_add_user_indexes_to_design_management_versions.rb

+# frozen_string_literal: true
+
+class AddUserIndexesToDesignManagementVersions < ActiveRecord::Migration[5.2]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_foreign_key :design_management_versions, :users, column: :user_id, on_delete: :nullify
+    add_concurrent_index :design_management_versions, :user_id, where: 'user_id IS NOT NULL'
+  end
+
+  def down
+    remove_concurrent_index :design_management_versions, :user_id
+    remove_foreign_key :design_management_versions, column: :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_09_19_162036) do
+ActiveRecord::Schema.define(version: 2019_09_26_041216) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_trgm"
@@ -1232,8 +1232,11 @@ ActiveRecord::Schema.define(version: 2019_09_19_162036) do
   create_table "design_management_versions", force: :cascade do |t|
     t.binary "sha", null: false
     t.bigint "issue_id"
+    t.integer "user_id"
+    t.datetime_with_timezone "created_at"
     t.index ["issue_id"], name: "index_design_management_versions_on_issue_id"
     t.index ["sha", "issue_id"], name: "index_design_management_versions_on_sha_and_issue_id", unique: true
+    t.index ["user_id"], name: "index_design_management_versions_on_user_id", where: "(user_id IS NOT NULL)"
   end
 
   create_table "draft_notes", force: :cascade do |t|
@@ -3930,6 +3933,7 @@ ActiveRecord::Schema.define(version: 2019_09_19_162036) do
   add_foreign_key "design_management_designs_versions", "design_management_designs", column: "design_id", name: "fk_03c671965c", on_delete: :cascade
   add_foreign_key "design_management_designs_versions", "design_management_versions", column: "version_id", name: "fk_f4d25ba00c", on_delete: :cascade
   add_foreign_key "design_management_versions", "issues", on_delete: :cascade
+  add_foreign_key "design_management_versions", "users", name: "fk_ee16b939e5", on_delete: :nullify
   add_foreign_key "draft_notes", "merge_requests", on_delete: :cascade
   add_foreign_key "draft_notes", "users", column: "author_id", on_delete: :cascade
   add_foreign_key "elasticsearch_indexed_namespaces", "namespaces", on_delete: :cascade