如何根据在Rails5中发布记录的用户来验证记录的唯一性？

class User < ApplicationRecord
  validates :email, uniqueness: true
end

def create
  @user = User.new(user_params)
  if @user.valid?
    # 执行保存记录的操作
  else
    # 处理验证失败的情况
  end
end

<% if @user.errors.any? %>
  <div id="error_explanation">
    <h2><%= pluralize(@user.errors.count, "error") %> prohibited this user from being saved:</h2>
    <ul>
      <% @user.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
    </ul>
  </div>
<% end %>