Hi Forum,

I have a table A which stores a "code" apart from aother details. The details related to the "code" like description, creation dates etc are stored in another table B having a composite id. When I map table A on column "code" to table B. It says that foreign key should have same number of columns as the primary key which is obvious. "code" column does form a part of the composite id for table B. How do i map this many-to-one relationship?

Please note that I am using Hibernate 2.0.3 and it does not have property-ref (I guess this would have been useful) for many-to-one.

Any pointers will be appreciated. TIA.

Since composite-id has several columns, many-to one should have a foreign key of the same structure

Beware to keep the same declaration order of your columns between composite-id and many-to-one

Does this mean that i should have all the columns forming the composite key of Table B in Table A. I am not really in a position to change the data model. Is there another work around?

If not, this is not a many-to-one. It is somehow a particular subset of many-to-many wo relation table, this is not supported by Hibernate and not very clean in a relational perspective

Will a surrogate key for Table B help? What changes will I need in my data model?

surrogate should solve your "table A structure can't change" issue but you'll have to update links in table A to map table B new PK.