Post.where(created_at: Time.zone.now.beginning_of_day..Time.zone.now.end_of_day)
PS: This answer has been modified as answer by Harish Shetty was better than mine. As my answer is accepted one. I have updated this answer for community support
Post.where(created_at: Time.zone.now.beginning_of_day..Time.zone.now.end_of_day)
PS: This answer has been modified as answer by Harish Shetty was better than mine. As my answer is accepted one. I have updated this answer for community support