You have a good point there. Thanks for the advice. I guess I would just
have run into that problem later. Maybe it would be a good idea to add
this advice to the user guide, where flattened relationships are
discussed. It took me, as a cayenne beginner, some time to figure out
how it is workin
Daniel,
I just re-ran your app after unchecking personID in your join table
(only bookID was set as the primary key). That causes SQL like this
to be produced:
INFO: DELETE FROM Person_is_author_of_book WHERE bookID = ?
May 12, 2008 2:45:31 PM org.apache.cayenne.access.QueryLogger logQueryParame
Setting both as PK is more correct, though, from a DB-perspective.
Your join table essentially has a compound primary key. I'd define it
that way in the DB, too. Setting both columns to be PK (it'll help
for the index, too).
Glad to hear it is working for you now.
/dev/mrg
On Mon, May 12, 200
Hi
Thanks again. Setting at least one of the attributes as primary key
solved the problem. As far as I tested, it is not important which of the
attributes is assigned the primary key, but there has to be at least one
PK. The PK generation strategy is set to default by the modeller. Any
change
[followup back to the user list]
Hi Daniel,
The first time I ran your test application it did indeed crash with
the missing WHERE clause (this is on Cayenne 3.x, too). I went into
your Cayenne Model, though, and on your Person_is_author_of_book table
(you didn't map it as a class, which is cool
Hi Dan,
I don't see anything offhand. Since you said you created a simple
test application, could you send it to me and I'll take a look at it?
Just tar it up and send directly to me (the mailing list doesn't
support attachments). Be sure to sanitize the DB connection
information first, though.
Hi!
I'm sorry I made a mistake there. When I was posting the code I was
leaving out some lines of comment and I seem to have lost one line of
code meanwhile.
So here is the (slightly changed) code again. This time free of typing
errors, I hope:
DataContext context = DataContext.creat
Hi Daniel, I'm not sure if you've solved your problem yet, but from
the code you posted, I don't see where you established any
relationship between book1 and author1/author2. You had objects with
no relationship defined, so you can't actually remove book1 from
author1.
/dev/mrg
On Tue, May 6, 2
Hello everyone!
I am new to cayenne and experiencing some problems, when modelling a
many-to-many relationship. After I could not solve the problem for an
application I am writing at the moment, I set up the following example
application, which is producing the same problems:
I modelled a sm
