Updated DB migration

* reordered columns
* moved fks to separate migrations

db/migrate/20200226100614_create_requirements.rb

@@ -7,16 +7,18 @@ class CreateRequirements < ActiveRecord::Migration[6.0]
 
   def change
     create_table :requirements do |t|
-      t.integer :state, limit: 2, default: 1, null: false
+      t.timestamps_with_timezone null: false
+      t.integer :project_id, null: false
+      t.integer :author_id
       t.integer :iid, null: false
       t.integer :cached_markdown_version
-      t.references :project, null: false, index: true, foreign_key: { on_delete: :cascade }
-      t.references :author, index: true, foreign_key: { to_table: :users, on_delete: :nullify }
-      t.timestamps_with_timezone null: false
+      t.integer :state, limit: 2, default: 1, null: false
       t.string :title, limit: 255, null: false
       t.text :title_html
 
-      t.index :title
+      t.index :project_id
+      t.index :author_id
+      t.index :title, name: "index_requirements_on_title_trigram", using: :gin, opclass: :gin_trgm_ops
       t.index :state
       t.index :created_at
       t.index :updated_at

db/migrate/20200226100624_requirements_add_project_fk.rb

+# frozen_string_literal: true
+
+class RequirementsAddProjectFk < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def up
+    with_lock_retries do
+      add_foreign_key(:requirements, :projects, column: :project_id, on_delete: :cascade) # rubocop: disable Migration/AddConcurrentForeignKey
+    end
+  end
+
+  def down
+    with_lock_retries do
+      remove_foreign_key(:requirements, column: :project_id)
+    end
+  end
+end

db/migrate/20200226100634_requirements_add_author_fk.rb

+# frozen_string_literal: true
+
+class RequirementsAddAuthorFk < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def up
+    with_lock_retries do
+      add_foreign_key(:requirements, :users, column: :author_id, on_delete: :nullify) # rubocop: disable Migration/AddConcurrentForeignKey
+    end
+  end
+
+  def down
+    with_lock_retries do
+      remove_foreign_key(:requirements, column: :author_id)
+    end
+  end
+end

db/schema.rb

@@ -3723,13 +3723,13 @@ ActiveRecord::Schema.define(version: 2020_02_27_165129) do
   end
 
   create_table "requirements", force: :cascade do |t|
-    t.integer "state", limit: 2, default: 1, null: false
-    t.integer "iid", null: false
-    t.integer "cached_markdown_version"
-    t.bigint "project_id", null: false
-    t.bigint "author_id"
     t.datetime_with_timezone "created_at", null: false
     t.datetime_with_timezone "updated_at", null: false
+    t.integer "project_id", null: false
+    t.integer "author_id"
+    t.integer "iid", null: false
+    t.integer "cached_markdown_version"
+    t.integer "state", limit: 2, default: 1, null: false
     t.string "title", limit: 255, null: false
     t.text "title_html"
     t.index ["author_id"], name: "index_requirements_on_author_id"
@@ -3737,7 +3737,7 @@ ActiveRecord::Schema.define(version: 2020_02_27_165129) do
     t.index ["project_id", "iid"], name: "index_requirements_on_project_id_and_iid", unique: true, where: "(project_id IS NOT NULL)"
     t.index ["project_id"], name: "index_requirements_on_project_id"
     t.index ["state"], name: "index_requirements_on_state"
-    t.index ["title"], name: "index_requirements_on_title"
+    t.index ["title"], name: "index_requirements_on_title_trigram", opclass: :gin_trgm_ops, using: :gin
     t.index ["updated_at"], name: "index_requirements_on_updated_at"
   end