如何通过rails activerecord获取今天创建的记录？

Question

当我想要获取今天创建的所有记录时,我应该如何编写条件语句？

Answer 1

Post.where(created_at: Time.zone.now.beginning_of_day..Time.zone.now.end_of_day)

PS:这个答案已被修改为Harish Shetty的答案比我的好.我的答案被接受了.我已更新此答案以获得社区支持

Answer 2

我知道这个问题有一个公认的答案.在表格大小增加时,在接受的答案中建议的解决方案可能会导致性能问题.

通常,如果基于created_at列执行查找,请在迁移文件中的表上添加索引.

add_index :posts, :created_at

现在,查找今天创建的记录:

Rails 3/4

Post.where("created_at >= ?", Time.zone.now.beginning_of_day)

查找在特定日期创建的帖子.

Post.where(:created_at => (date.beginning_of_day..date.end_of_day))

--------- 或 -------------

向模型添加静态方法

class Post < ActiveRecord::Base
  def self.today
    where("created_at >= ?", Time.zone.now.beginning_of_day)
  end
end

Post.today #returns posts today

Rails 2

Post.all(:conditions => ["created_at >= ?", Time.zone.now.beginning_of_day])

--------- 或 -------------

将named_scope添加到模型中

class Post < ActiveRecord::Base    
  named_scope :today, lambda { 
    {
      :conditions => ["created_at >= ?", Time.zone.now.beginning_of_day]
    }
  }
end

Post.today #returns posts today

Answer 3

MySQL的:

Model.all :condition => ["DATE(created_at) = ?", Date.today] # rails 2
Model.where("DATE(created_at) = ?", Date.today) # rails 3

PostgreSQL的:

Model.all :condition => ["created_at::date = ?", Date.today] # rails 2
Model.where("created_at::date = ?", Date.today) # rails 3

Answer 4

Mohit Jain的答案适用于Rails3

Model.where "DATE(created_at) = DATE(?)", Time.now

Answer 5

Rails 5.1有一个all_day在这里有用的助手。

Post.where(created_at: Date.today.all_day)

要么

Post.where(created_at: Date.parse("YYYY-MM-DD").all_day)

Answer 6

Post.where(created_at: Time.zone.now.beginning_of_day..Time.zone.now.end_of_day)

这个"名称范围"的属性与table_name.

Answer 7

model.rb

scope :posted_today, -> { posted_between_period(Time.now.midnight, Time.now.end_of_day) }

posts_controller.rb

Post.posted_today