Question

在我的控制器中，我想做类似以下的事情：

@book = Book.find(:all, :conditions = > [" created_at > with in the last 1 minute "]

if @book.nil?
  # Just incase we didn't create a book, we'll initialize one
  @book = Book.create()
end

@chapters = @book.chapters.build etc.............

* 总而言之，当用户上传章节时，如果他们最近创作了一本书，我希望这一章能够自动转到那本书并制作新书。

思考？谢谢大家

Answer 1

您的代码可能类似

time = Time.now
@book = Book.find(:all, :conditions = > [" created_at >= '#{Time.utc(time.year, time.month, time.day, time.hour, time.min - 1)}'"]) // .first if you're sure that it'll return just one record

if @book.blank? //.blank? not .nil? because the result of find is [] not nil
  # Just incase we didn't create a book, we'll initialize one
  @book = Array.new() //if you're sure that find'll return just one book you may don't change your code here
  @book.first = Book.create()
end

//if you're sure that find'll return just one book you may don't change your code here
@book.each do |book|
 @chapters = @book.chapters.build etc.............
end

如果您正在寻找由某个用户创建的图书，则必须将user_id传递给此方法并且您的条件将

:conditions = > [" created_at >= '?' AND author_id = ?", Time.utc(time.year, time.month, time.day, time.hour, time.min - 1), params[:author_id]])

Rails - 基于TimeStamp查找或创建？可能？

1 个答案: