On Nov 5, 2007, at 8:22 PM, Patrick Linskey wrote:
I believe it's unidirectional ManyToOne (if that's legal). Each
InputFile is associated with one Show and one Show only, but multiple
InputFiles can be associated to the same Show.
I believe that what you're describing is a unidirectional one-to-one
with a join table. I think that you can model this with a secondary
table.
I tried that after sending the mail below, and it worked.
@ManyToOne sounds like it's describing an ER concept, but I believe
that in reality, it's reserved for the backpointer of a @OneToMany.
Why?
-Patrick
On 11/5/07, Geir Magnusson Jr. <[EMAIL PROTECTED]> wrote:
To review, I have three tables :
Show, InputFile and a join table, Show2InputFile.
Show happens to be a subclass of InventoryItem using JOINED
inheritance strategy. Not sure if that matters. (I've seen some
weird behavior w/ Hibernate w/ JOINED, so I'm suspicious of it for no
rational reason)
Show has a PK "id", as does InputFile.
Show2InputFile looks like :
+-------------+------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+------------------+------+-----+---------+-------+
| showId | int(11) unsigned | NO | PRI | | |
| inputFileId | int(11) unsigned | NO | PRI | | |
+-------------+------------------+------+-----+---------+-------+
I believe it's unidirectional ManyToOne (if that's legal). Each
InputFile is associated with one Show and one Show only, but multiple
InputFiles can be associated to the same Show.
Currently I have in InputFile :
@ManyToOne
@JoinTable(name="Show2InputFile",
joinColumns = @JoinColumn(name="inputFileId"),
inverseJoinColumns = @JoinColumn(name="showId"))
public Show getShow() {
return show;
}
and while Hibernate thinks that's just peachy, OpenJPA 1.0.0 gags on
it with
Caused by: <openjpa-1.1.0-SNAPSHOT-r420667:588533 fatal user error>
org.apache.openjpa.persistence.ArgumentException: You have supplied
columns for "com.joost.model.logistics.InputFile.show<element:class
java.lang.Object>", but this mapping cannot have columns in this
context.
Now, while I don't want to add anything to the Show class, since this
really is unidirectional, I did add :
@OneToMany
@JoinTable(name="Show2InputFile",
inverseJoinColumns = @JoinColumn(name="inputFileId"),
joinColumns = @JoinColumn(name="showId"))
public Set<InputFile> getInputFiles(){
return null;
}
public void setInputFiles(Set<InputFile> list) {
//noop
}
just to see if that would make OpenJPA happy, but as far as I can
see, it doesn't. I believe I get the same error message.
I really want to switch to OpenJPA, but this is stopping me. Does
anyone have any idea what I'm doing wrong?
geir
On Nov 5, 2007, at 3:05 PM, Patrick Linskey wrote:
Where are the foreign keys?
Bear in mind that @OneToOne, @OneToMany, @ManyToMany, and @ManyToOne
are JPA annotations, not ER annotations. The concepts differ a bit.
-Patrick
On Nov 5, 2007 11:33 AM, Geir Magnusson Jr. <[EMAIL PROTECTED]> wrote:
On Nov 5, 2007, at 2:07 PM, Patrick Linskey wrote:
What happens if you just use a @OneToOne instead of the
@ManyToOne?
The problem is that it's not OneToOne
Can you describe this in more detail? (I.e., in terms of what your
schema looks like.)
Well, there's a Show table, w/ a pk, and the Show class really
has no
interest in the InputFile class.
There's an inputfile table, w/ a pk. The InputFile class does
have a
ManyToOne with Show :
In real world problem, each Show we have on the platform is a
singleton ("I dream of Genie Epsode 11"), but a content owner may
give us updated source material - say they have a new transcoding.
We want to add a new InputFile into the database, point it at the
Show, but the Show itself doesn't care about it's source.
Does that help?
eir
-Patrick
On Nov 5, 2007 10:40 AM, Geir Magnusson Jr. <[EMAIL PROTECTED]>
wrote:
On Nov 5, 2007, at 12:44 PM, Patrick Linskey wrote:
I'm a newbie, so I don't quite grok the question. Show itself
doesn't have any references to InputFile.
Aha! IIRC, @ManyToOne is only meaningful when used as the back
side of
a @OneToMany.
We don't have that. There are reasons, and its intentional.
What happens if you just use a @OneToOne instead of the
@ManyToOne?
The problem is that it's not OneToOne
-Patrick
On Nov 5, 2007 9:16 AM, Geir Magnusson Jr. <[EMAIL PROTECTED]>
wrote:
On Nov 5, 2007, at 11:48 AM, Patrick Linskey wrote:
Hi,
What does the other side of the relation look like?
I'm a newbie, so I don't quite grok the question. Show itself
doesn't have any references to InputFile.
Also, what does
the Show class look like?
in what way? Show is a subclass in a JOINED inheritance
strategy, if
that makes any difference.
geir
-Patrick
On Nov 5, 2007 8:08 AM, Geir Magnusson Jr. <[EMAIL PROTECTED]>
wrote:
I'm a newbie, so forgive me if I'm not asking the question
the
right
way.
I have a join table in my DB :
+-------------+------------------+------+-----+---------
+-------+
| Field | Type | Null | Key | Default |
Extra |
+-------------+------------------+------+-----+---------
+-------+
| showId | int(11) unsigned | NO | PRI |
| |
| inputFileId | int(11) unsigned | NO | PRI |
| |
+-------------+------------------+------+-----+---------
+-------+
where showId and inputFileID are PKs in the show table and
inputfile
table.
In my code for the InputFile class :
@ManyToOne
@JoinTable(name="Show2InputFile",
joinColumns = @JoinColumn(name="inputFileId"),
inverseJoinColumns = @JoinColumn(name="showId"))
public Show getShow() {
return show;
}
When JPA is instrumenting my classes, it complains :
Caused by: <openjpa-1.1.0-SNAPSHOT-r420667:588533 fatal user
error>
org.apache.openjpa.persistence.ArgumentException: You have
supplied
columns for
"com.joost.model.logistics.InputFile.show<element:class
java.lang.Object>", but this mapping cannot have columns in
this
context.
I don't quite understand the error. I use this same thing
elsewhere
(I think) w/o a problem. Can someone give me a hint?
geir
--
Patrick Linskey
202 669 5907
--
Patrick Linskey
202 669 5907
--
Patrick Linskey
202 669 5907
--
Patrick Linskey
202 669 5907
--
Patrick Linskey
202 669 5907
