小编Ram*_*jan的帖子

我在docker上安装了Ubuntu 14.04镜像.之后,当我尝试在ubuntu映像中安装软件包时,我无法找到软件包错误:

apt-get install curl

Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package curl

如何解决这个错误？

目前在Ruby上遇到了一些严重的问题,我感觉这是版本控制.

我有一个看起来像这样的Gemfile

source "https://rubygems.org"

ruby "2.5.2"

gem "rails", "4.2.1"
gem "unicorn", "4.8.3"
gem "mysql2"
gem "sass-rails", "~> 4.0.3"
gem "uglifier", ">= 1.3.0"
gem "coffee-rails", "~> 4.0.0"
gem "turbolinks"
gem "ancestry"
gem "kaminari"
gem "saxerator"
gem "factory_girl_rails"
gem "delayed_job_active_record"
gem "tree_delta", "~> 2.0.0"
gem "daemons"
gem "which-user",      git: "https://ad131a5ab23a69365434b0e7e36d6275b6a1e9fb:x-oauth-basic@github.com/whichdigital/which-user.git", ref: '18eb7'
gem "eva_rails",       git: "https://ad131a5ab23a69365434b0e7e36d6275b6a1e9fb:x-oauth-basic@github.com/whichdigital/eva_rails.git", tag: "v1.0.6"
gem "dam_client",      git: "https://ad131a5ab23a69365434b0e7e36d6275b6a1e9fb:x-oauth-basic@github.com/whichdigital/digital_asset_manager_client.git", tag: "1.0.0"
gem "fragment_client", git: "https://ad131a5ab23a69365434b0e7e36d6275b6a1e9fb:x-oauth-basic@github.com/whichdigital/fragment_client.git", ref: '3c197'
gem 'frontend_containers', git: "https://ad131a5ab23a69365434b0e7e36d6275b6a1e9fb:x-oauth-basic@github.com/whichdigital/frontend_containers.git"
gem "cucumber-rails", require: false
gem "parallel_tests"
gem "elasticsearch" …

这是我正在使用的两个模型，

用户模型

class User < ActiveRecord::Base
  has_many :products
end

产品型号

class Product < ActiveRecord::Base
  belongs_to :user
end

现在我想找出哪个用户拥有最大数量的产品。

我知道我可以通过为用户和相关产品构建一个循环来找出答案，但是有没有办法通过活动记录查询来找出答案？