Re: one-to-many design question
Slight correction. In your first example: class Chapter(models.Model): >book = models.ForeignKey(Chapter) > The parameter to ForeignKey should be book: class Chapter(models.Model): book = models.ForeignKey(Book) As mentioned earlier, you can locate a chapter's book as chapter.book, and you can locate a book's chapters using book.chapter_set.all(). -- Scott Moonen On Fri, May 9, 2008 at 12:08 PM, Mike Chambers <[EMAIL PROTECTED]> wrote: > > I am working on an app to host some books online. I cant figure out the > best way to represent a one to many relationship. > > Basically, a Book has multiple Chapters, but a Chapter can only be in > one book. > > Looking at the docs, this seems to be the way to represent this: > > > -- > class Book(models.Model): > > > class Chapter(models.Model): >book = models.ForeignKey(Chapter) > -- > > Is that right? This seems a little counterintuitive to me, and something > like this seems to make more sense: > > > -- > class Book(models.Model): >chapters = models.ManyToManyField(Chapter) > > class Chapter(models.Model): > -- > > Of course, that means that a chapter can be placed on multiple books. > > The second example, also seems to make it a little easier to work with > Books, as I can do: > > Book.objects.all() > > and get the Chapters associated with each book. > > So, what is the "correct" way to model this relationship? > > Thanks for any input... > > mike > > > > > -- http://scott.andstuff.org/ | http://truthadorned.org/ --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~--~~~~--~~--~--~---
Re: one-to-many design question
Thanks for confirming. Book.chapter_set.all() gets all of the chapters for the book. Thanks! mike [EMAIL PROTECTED] wrote: > The first way is the correct way, to get all the chapters for a given > book you would do book_obj.chapter_set.all() , you can set what this > attribute is named by doing ForeignKey(Chapter, > related_name='this_thing'). > > On May 9, 11:08 am, Mike Chambers <[EMAIL PROTECTED]> wrote: >> I am working on an app to host some books online. I cant figure out the >> best way to represent a one to many relationship. >> >> Basically, a Book has multiple Chapters, but a Chapter can only be in >> one book. >> >> Looking at the docs, this seems to be the way to represent this: >> >> -- >> class Book(models.Model): >> >> class Chapter(models.Model): >> book = models.ForeignKey(Chapter) >> -- >> >> Is that right? This seems a little counterintuitive to me, and something >> like this seems to make more sense: >> >> -- >> class Book(models.Model): >> chapters = models.ManyToManyField(Chapter) >> >> class Chapter(models.Model): >> -- >> >> Of course, that means that a chapter can be placed on multiple books. >> >> The second example, also seems to make it a little easier to work with >> Books, as I can do: >> >> Book.objects.all() >> >> and get the Chapters associated with each book. >> >> So, what is the "correct" way to model this relationship? >> >> Thanks for any input... >> >> mike > > --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~--~~~~--~~--~--~---
Re: one-to-many design question
The first way is the correct way, to get all the chapters for a given book you would do book_obj.chapter_set.all() , you can set what this attribute is named by doing ForeignKey(Chapter, related_name='this_thing'). On May 9, 11:08 am, Mike Chambers <[EMAIL PROTECTED]> wrote: > I am working on an app to host some books online. I cant figure out the > best way to represent a one to many relationship. > > Basically, a Book has multiple Chapters, but a Chapter can only be in > one book. > > Looking at the docs, this seems to be the way to represent this: > > -- > class Book(models.Model): > > class Chapter(models.Model): > book = models.ForeignKey(Chapter) > -- > > Is that right? This seems a little counterintuitive to me, and something > like this seems to make more sense: > > -- > class Book(models.Model): > chapters = models.ManyToManyField(Chapter) > > class Chapter(models.Model): > -- > > Of course, that means that a chapter can be placed on multiple books. > > The second example, also seems to make it a little easier to work with > Books, as I can do: > > Book.objects.all() > > and get the Chapters associated with each book. > > So, what is the "correct" way to model this relationship? > > Thanks for any input... > > mike --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~--~~~~--~~--~--~---
one-to-many design question
I am working on an app to host some books online. I cant figure out the best way to represent a one to many relationship. Basically, a Book has multiple Chapters, but a Chapter can only be in one book. Looking at the docs, this seems to be the way to represent this: -- class Book(models.Model): class Chapter(models.Model): book = models.ForeignKey(Chapter) -- Is that right? This seems a little counterintuitive to me, and something like this seems to make more sense: -- class Book(models.Model): chapters = models.ManyToManyField(Chapter) class Chapter(models.Model): -- Of course, that means that a chapter can be placed on multiple books. The second example, also seems to make it a little easier to work with Books, as I can do: Book.objects.all() and get the Chapters associated with each book. So, what is the "correct" way to model this relationship? Thanks for any input... mike --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~--~~~~--~~--~--~---
