Improve indexes and refs in pipeline stages migrations

db/migrate/20170525132202_create_pipeline_stages.rb

@@ -3,12 +3,23 @@ class CreatePipelineStages < ActiveRecord::Migration
 
   DOWNTIME = false
 
-  def change
+  disable_ddl_transaction!
+
+  def up
     create_table :ci_stages do |t|
       t.integer :project_id
       t.integer :pipeline_id
       t.timestamps null: true
       t.string :name
     end
+
+    add_concurrent_foreign_key :ci_stages, :projects, column: :project_id, on_delete: :cascade
+    add_concurrent_foreign_key :ci_stages, :ci_pipelines, column: :pipeline_id, on_delete: :cascade
+    add_concurrent_index :ci_stages, :project_id
+    add_concurrent_index :ci_stages, :pipeline_id
+  end
+
+  def down
+    drop_table :ci_stages
   end
 end

db/migrate/20170526185602_add_stage_id_to_ci_builds.rb

@@ -3,7 +3,19 @@ class AddStageIdToCiBuilds < ActiveRecord::Migration
 
   DOWNTIME = false
 
-  def change
+  disable_ddl_transaction!
+
+  def up
     add_column :ci_builds, :stage_id, :integer
+
+    add_concurrent_foreign_key :ci_builds, :ci_stages, column: :stage_id, on_delete: :cascade
+    add_concurrent_index :ci_builds, :stage_id
+  end
+
+  def down
+    remove_concurrent_index :ci_builds, :stage_id
+    remove_foreign_key :ci_builds, column: :stage_id
+
+    remove_column :ci_builds, :stage_id, :integer
   end
 end

db/post_migrate/20170526185842_migrate_pipeline_stages.rb

@@ -16,8 +16,4 @@ class MigratePipelineStages < ActiveRecord::Migration
           ORDER BY MAX(stage_idx)
     SQL
   end
-
-  def down
-    execute('TRUNCATE TABLE ci_stages')
-  end
 end

db/post_migrate/20170526190708_create_foreign_keys_for_pipeline_stages.rb

-class CreateForeignKeysForPipelineStages < ActiveRecord::Migration
-  include Gitlab::Database::MigrationHelpers
-
-  DOWNTIME = false
-
-  disable_ddl_transaction!
-
-  def up
-    disable_statement_timeout
-
-    execute <<~SQL
-      DELETE FROM ci_stages
-        WHERE NOT EXISTS (
-          SELECT true FROM projects
-            WHERE projects.id = ci_stages.project_id
-        )
-    SQL
-
-    execute <<~SQL
-      DELETE FROM ci_builds
-        WHERE NOT EXISTS (
-          SELECT true FROM ci_stages
-            WHERE ci_stages.id = ci_builds.stage_id
-        )
-    SQL
-
-    add_concurrent_foreign_key :ci_stages, :projects, column: :project_id, on_delete: :cascade
-    add_concurrent_foreign_key :ci_builds, :ci_stages, column: :stage_id, on_delete: :cascade
-  end
-
-  def down
-    remove_foreign_key :ci_stages, column: :project_id
-    remove_foreign_key :ci_builds, column: :stage_id
-  end
-end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20170526190708) do
+ActiveRecord::Schema.define(version: 20170526185921) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -243,6 +243,7 @@ ActiveRecord::Schema.define(version: 20170526190708) do
   add_index "ci_builds", ["commit_id", "type", "ref"], name: "index_ci_builds_on_commit_id_and_type_and_ref", using: :btree
   add_index "ci_builds", ["project_id"], name: "index_ci_builds_on_project_id", using: :btree
   add_index "ci_builds", ["runner_id"], name: "index_ci_builds_on_runner_id", using: :btree
+  add_index "ci_builds", ["stage_id"], name: "index_ci_builds_on_stage_id", using: :btree
   add_index "ci_builds", ["status", "type", "runner_id"], name: "index_ci_builds_on_status_and_type_and_runner_id", using: :btree
   add_index "ci_builds", ["status"], name: "index_ci_builds_on_status", using: :btree
   add_index "ci_builds", ["token"], name: "index_ci_builds_on_token", unique: true, using: :btree
@@ -330,12 +331,14 @@ ActiveRecord::Schema.define(version: 20170526190708) do
   create_table "ci_stages", force: :cascade do |t|
     t.integer "project_id"
     t.integer "pipeline_id"
-    t.string "name"
     t.datetime "created_at"
     t.datetime "updated_at"
+    t.string "name"
   end
 
   add_index "ci_stages", ["pipeline_id", "name"], name: "index_ci_stages_on_pipeline_id_and_name", using: :btree
+  add_index "ci_stages", ["pipeline_id"], name: "index_ci_stages_on_pipeline_id", using: :btree
+  add_index "ci_stages", ["project_id"], name: "index_ci_stages_on_project_id", using: :btree
 
   create_table "ci_trigger_requests", force: :cascade do |t|
     t.integer "trigger_id", null: false
@@ -1497,6 +1500,7 @@ ActiveRecord::Schema.define(version: 20170526190708) do
   add_foreign_key "ci_pipeline_schedules", "users", column: "owner_id", name: "fk_9ea99f58d2", on_delete: :nullify
   add_foreign_key "ci_pipelines", "ci_pipeline_schedules", column: "pipeline_schedule_id", name: "fk_3d34ab2e06", on_delete: :nullify
   add_foreign_key "ci_pipelines", "ci_pipelines", column: "auto_canceled_by_id", name: "fk_262d4c2d19", on_delete: :nullify
+  add_foreign_key "ci_stages", "ci_pipelines", column: "pipeline_id", name: "fk_fb57e6cc56", on_delete: :cascade
   add_foreign_key "ci_stages", "projects", name: "fk_2360681d1d", on_delete: :cascade
   add_foreign_key "ci_trigger_requests", "ci_triggers", column: "trigger_id", name: "fk_b8ec8b7245", on_delete: :cascade
   add_foreign_key "ci_triggers", "users", column: "owner_id", name: "fk_e8e10d1964", on_delete: :cascade