如何計算Ruby on Rails應用程序中的記錄？

Question

我想要在視圖中顯示所有不同的記錄。我在我的accounts_controler.rb文件@account = Account.count("created_at", :distinct => true)中有以下內容，或者我應該使用Account.distinct.count('date')？如果我正確地讀了導軌4 :distinct => true現已棄用

我不確定這是否正確。這裏是整個控制器文件：

class AccountsController < ApplicationController 
    before_action :authenticate_user! 
    before_action :set_account, only: [:show, :edit, :update, :destroy] 

    respond_to :html 

    def search 
    if params[:search].present? 
    @account = Account.search(params[:search]) 
    else 
    @account = Account.all 
    end 
    end 

    def index 
    @account = Account.all.order("created_at DESC").page(params[:page]).per(10) 
    @account = Account.count("created_at", :distinct => true) 
    end 

end 

    def show 
    @notes = Note.where(account_id: @account.id) #Where a note belong to the current account 
    end 

    def new 
    @account = Account.new 
    respond_with(@account) 
    end 

    def edit 
    end 

    def create 
    @account = Account.new(account_params) 
    @account.save 
    respond_with(@account) 
    end 

    def update 
    @account.update(account_params) 
    respond_with(@account) 
    end 

    def destroy 
    @account.destroy 
    respond_with(@account) 
    end 

    private 
    def set_account 
     @account = Account.find(params[:id]) 
    end 

    def account_params 
     params.require(:account).permit(:first_name, :last_name, :return_client, :program_id, :insurance_id, :address, :phone) 
    end 

我beleive應該有一個紅寶石標籤包括在index.html.erb文件，但我不知道語法。

Answer 1

可以使用uniq關鍵字返回所有不重複的記錄如下：

def index 
    @accounts = Account.uniq.order("created_at DESC").page(params[:page]).per(10) 

    @accounts_count = Account.uniq.count 
end 

，然後你會在你的index.html.erb文件訪問實例變量@accounts。

Answer 2

你說得對。

的Rails 3：

Account.count(:created_at, distinct: true) 

軌道4,5：

Account.distinct.count('date')