Remove setup_postgres task and update schema RB

changelogs/unreleased/update-schema-rb.yml

+---
+title: Remove Postgresql specific setup tasks and move to schema.rb
+merge_request:
+author:
+type: other

db/migrate/20180113220114_rework_redirect_routes_indexes.rb

@@ -20,9 +20,7 @@ class ReworkRedirectRoutesIndexes < ActiveRecord::Migration[4.2]
   def up
     disable_statement_timeout do
       # this is a plain btree on a single boolean column. It'll never be
-      # selective enough to be valuable. This class is called by
-      # setup_postgresql.rake so it needs to be able to handle this
-      # index not existing.
+      # selective enough to be valuable.
       if index_exists?(:redirect_routes, :permanent)
         remove_concurrent_index(:redirect_routes, :permanent)
       end

db/post_migrate/20180306164012_add_path_index_to_redirect_routes.rb

@@ -14,9 +14,7 @@ class AddPathIndexToRedirectRoutes < ActiveRecord::Migration[4.2]
   # RedirectRoute.matching_path_and_descendants
   #
   # This same index is also added in the `ReworkRedirectRoutesIndexes` so this
-  # is a no-op in most cases. But this migration is also called from the
-  # `setup_postgresql.rake` task when setting up a new database, in which case
-  # we want to create the index.
+  # is a no-op in most cases.
   def up
     return unless Gitlab::Database.postgresql?
 
@@ -31,8 +29,5 @@ class AddPathIndexToRedirectRoutes < ActiveRecord::Migration[4.2]
     # Do nothing in the DOWN. Since the index above is originally created in the
     # `ReworkRedirectRoutesIndexes`. This migration wouldn't have actually
     # created any new index.
-    #
-    # This migration is only here to be called form `setup_postgresql.rake` so
-    # any newly created database would have this index.
   end
 end

db/schema.rb

@@ -2917,6 +2917,7 @@ ActiveRecord::Schema.define(version: 2019_09_26_041216) do
     t.boolean "emails_disabled"
     t.integer "max_pages_size"
     t.integer "max_artifacts_size"
+    t.index "lower((name)::text)", name: "index_projects_on_lower_name"
     t.index ["archived", "pending_delete", "merge_requests_require_code_owner_approval"], name: "projects_requiring_code_owner_approval", where: "((pending_delete = false) AND (archived = false) AND (merge_requests_require_code_owner_approval = true))"
     t.index ["created_at"], name: "index_projects_on_created_at"
     t.index ["creator_id"], name: "index_projects_on_creator_id"
@@ -3113,6 +3114,7 @@ ActiveRecord::Schema.define(version: 2019_09_26_041216) do
     t.string "path", null: false
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
+    t.index "lower((path)::text) varchar_pattern_ops", name: "index_redirect_routes_on_path_unique_text_pattern_ops", unique: true
     t.index ["path"], name: "index_redirect_routes_on_path", unique: true
     t.index ["source_type", "source_id"], name: "index_redirect_routes_on_source_type_and_source_id"
   end
@@ -3641,6 +3643,7 @@ ActiveRecord::Schema.define(version: 2019_09_26_041216) do
     t.string "first_name", limit: 255
     t.string "last_name", limit: 255
     t.string "static_object_token", limit: 255
+    t.index "lower((name)::text)", name: "index_on_users_name_lower"
     t.index ["accepted_term_id"], name: "index_users_on_accepted_term_id"
     t.index ["admin"], name: "index_users_on_admin"
     t.index ["bot_type"], name: "index_users_on_bot_type"

lib/tasks/gitlab/setup.rake

@@ -31,7 +31,6 @@ namespace :gitlab do
     terminate_all_connections unless Rails.env.production?
 
     Rake::Task["db:reset"].invoke
-    Rake::Task["setup_postgresql"].invoke
     Rake::Task["db:seed_fu"].invoke
   rescue Gitlab::TaskAbortedByUserError
     puts "Quitting...".color(:red)

lib/tasks/migrate/setup_postgresql.rake

-desc 'GitLab | Sets up PostgreSQL'
-task setup_postgresql: :environment do
-  require Rails.root.join('db/migrate/20180215181245_users_name_lower_index.rb')
-  require Rails.root.join('db/migrate/20180504195842_project_name_lower_index.rb')
-  require Rails.root.join('db/post_migrate/20180306164012_add_path_index_to_redirect_routes.rb')
-
-  UsersNameLowerIndex.new.up
-  ProjectNameLowerIndex.new.up
-  AddPathIndexToRedirectRoutes.new.up
-end
-
 desc 'GitLab | Generate PostgreSQL Password Hash'
 task :postgresql_md5_hash do
   require 'digest'