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ManyToOne relation with composite keys

Kulbhushan Sharma

Joined: Oct 15, 2008
Posts: 2

I am having problems with JPA using Toplink. I have used the default generated code for entities with NetBeans 6.1.

There are three tables defined in MySQL as

The entities generated lead rightly to Composite Keys with @Embedded and EmbeddedID annotations for the tables FilesOnServer and FolderDetails with additional entities FilesOnServerPK FolderDetailsPK .

I persist the relationship (between the FilesOnServer and FolderDetails entities with the code below

The FileOnServer entity is persisted without error but the PARENT_ID field remains null when I was expecting it to be updated with the FOLDER_ID field from the FolderDetails Table/entity.

In the log the following sql command appears
bind => [n0n0n.txt, 51, 1001, 1]

The thing I noted it that there is no refernce to the PARENT_ID column here...

Any ideas what I may be doing wrong?

Kulbhushan Sharma

Joined: Oct 15, 2008
Posts: 2
No response.

The workaround we use is to expand the primary key for FilesOnServer to also include the ParentID which works but is a hack.
I agree. Here's the link:
subject: ManyToOne relation with composite keys
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