So if you have a reference to a new card and do

cardList.add(cardRefference)

all you are loading into memory is the card list and the new card.

Is this what you are trying to avoid?

On Mar 10, 4:06 pm, tempy <[email protected]> wrote:
> Actually cards can only be owned by one deck... so that's not a
> problem.  Deck<--1...0toN-->card.
>
> The thing that I am looking for is a way to add new cards without
> loading a deck's entire card collection, and to add decks without
> loading a User's entire deck collection.
>
> On Mar 10, 9:15 pm, WillSpecht <[email protected]> wrote:
>
> > The way I understand it, if an object can be owned by more than one
> > object it must be unowned.  I would assume that cards can be in
> > multiple decks so they must be unowned.  I would assume each deck
> > would belong to one user so decks could be owned.  I don't know a good
> > way to store cards that can be queried in one query unless you have
> > each card store what decks they are in.  This could be even more
> > difficult if cards appear more than once in a deck.  If that is true I
> > would suggest a join table.
>
> > On Mar 10, 2:20 pm, tempy <[email protected]> wrote:
>
> > > I have the following datastructure:
>
> > > "Users" are the root entities, and each "user" can have one or more
> > > "decks", and each deck can have one or more "cards."
>
> > > When a user wants to add a deck, I would like to be able to add the
> > > deck to the user's collection of decks without first fetching all of
> > > the user's decks (potentially a large amount of data), then adding the
> > > new deck to that collection, and then persisting the user.  Rather, I
> > > would like to simply instantiate the deck and append it to the user's
> > > collection of decks, without ever retrieving the entire collection.
>
> > > Similarly, if a user wants to add a new card to an existing deck, I
> > > would like to add the card to the deck without first retrieving the
> > > entire deck (that is, the deck with all of its cards).
>
> > > I would like to preserve the option of fetching a user with a
> > > populated collection of all their decks and to retrieve a deck with a
> > > populated collection of all its cards, which is possible with owned
> > > relationships.  But to accomplish what I have mentioned above, would I
> > > be forced to use unowned relationships? (Collections of keys instead
> > > of collections of objects.)
>
> > > Thanks,
> > > Mike
>
>

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