rails accepts_nested_attributes_for无法更新

Question

我使用accepts_nested_attributes_for更新has_many嵌套表，为什么不更新却插入

diaries_controller.rb

def update
  @diary=Diary.find(params[:id])
  if @diary.update(update_diary_params)
    render_ok
  else
    render_err :update_error
  end
end


  def update_diary_params
      params.require(:diary).permit(:date,:weather,:remark, :diary_pictures_attributes=> [:diary_picture,:clothing_picture,:id,:_destroy])
  end

model / diary.rb

class Diary < ApplicationRecord
  has_many :diary_pictures,dependent: :destroy

  accepts_nested_attributes_for :diary_pictures,allow_destroy: true

end

model / diary_picture.rb

class DiaryPicture < ApplicationRecord
  belongs_to :diary
  validates_presence_of :diary
end

enter image description here