What if I don't want the primary key of the many-to-many association table created by the composite-element with many-to-one technique to include the extra columns? I only want the two foreign keys to make up the composite primary key, and not the extra column information. I actually have a use-case for this, as I am mapping to a legacy database.

Take the example on page 229 of HiA to illustrate (the section with the title Using a collection of components for a many-to-many association). I want the primary key of the CATEGORY_ITEMS table to only be the composite of CATEGORY_ID and ITEM_ID. I still want the extra columns, like USERNAME and DATE_ADDED, I just don't want them to be a part of the composite primary key. How do I do this?

Warmest regards, Matt

A <key> can have <columns> inside it to define multiple keys - as per the DTD and documentation ;)

I don't think your answer applies in my case, as the <composite-element> is automatically creating keys. With regards to the example on page 229 of HiA, could you show us how you would do what you suggest? Here is the code:



This code will make a comosite primary key out of all four columns: CATEGORY_ID, ITEM_ID, USERNAME and DATE_ADDED. However, I only want the comosite primary key to be made up of the two columns CATEGORY_ID and ITEM_ID. I still want the other two columns to be in the table and not-null, but I don't want them to be a part of the composite primary key. How do I do this?

Warmest regards, Matt

If you want additional properties that is not part of the key - then why don't you just use a stanard <one-to-many> association ?

Also look at <idbag> (which give you support for additonal props - but requires a surrogate key)