Also, be aware that if a book can have more than one author JDO-GAE
has no support for either many-many or unowned relationships. In
that caes you would need to use low-level Keys or a non-standard
library like Twig http://code.google.com/p/twig-persist/ which does
support those relationships.
On 18 Jan 2010, at 11:45, Dave wrote:
I am having the same problems of how to do this. However, I do not
like Jason's solution because it seems as if I would get the book data
back even if I wanted the author data only.
On Jan 12, 5:58 pm, "Jason (Google)" <[email protected]> wrote:
If you're using JDO, then just as Juan said, you can fetch the
author's
books when you fetch the author entities themselves. Just make sure
to
specify that the books field is in the default fetch group:
@Persistent(defaultFetchGroup = "true")
private List<Book> books;
//...
public List<Book> getBooks() {
return books;
}
- Jason
On Mon, Jan 11, 2010 at 12:53 PM, Juan <[email protected]> wrote:
Are you using JDO/JPA? or querying thru GQL?
in the first case, make sure you eager fetch de book collection when
retrieving the object form DB. second case... just follow Bert´s
suggestion
On Jan 10, 7:40 pm, fhucho <[email protected]> wrote:
Hi, sorry for beginner question. I have authors and books in the
database. Every author has list of books in a one to many owned
relationship. I know the author's name, how can I retrieve the
author
and his books from database? I know how to get the author but not
his
books (Author.books).
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