DB Schema with uuids

create_table "messages", id: :uuid, default: "uuid_generate_v4()", force: :cascade do |t|
    t.boolean  "read",       default: false
    t.uuid     "chat_id"
    t.uuid     "user_id"
    t.datetime "created_at",                 null: false
    t.datetime "updated_at",                 null: false
    t.string   "event_type"
    t.uuid     "data_id"
    t.string   "data_type"
end

add_index "messages", ["chat_id"], name: "index_messages_on_chat_id", using: :btree
add_index "messages", ["data_id"], name: "index_messages_on_data_id", using: :btree
add_index "messages", ["id"], name: "index_messages_on_id", unique: true, using: :btree
add_index "messages", ["user_id"], name: "index_messages_on_user_id", using: :btree

class CreateMessage < ActiveRecord::Migration
  def change
    create_table :messages, id: :uuid do |t|
      t.string :type
      t.boolean :read, default: false

      t.references :chat, type: :uuid, index: true
      t.references :user, type: :uuid, index: true

      t.timestamps null: false
    end
    add_index :messages, :id, unique: true
  end
end