Hi. We are having trouble mapping a one-to-many relationships with both ends' identity being composite keys (components). When trying to load it, we get
Hibernate version: 3.1

Mapping documents:
<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.acme" >
<class name="ItemDefinition" table="XRV_SER_DFN_ITMS">
<composite-id>
<key-property name="seriesName" column="SER_ID_R"></key-property>
<key-property name="effectiveDate" column="EFCT_D" ></key-property>
<key-property name="districtCode" column="DIST_C"></key-property>
<key-property name="itemCode" column="ITM_ID_C"></key-property>
</composite-id>
<property name="itemDescription" column="ITM_DESC_X" />
<property name="itemType" column="ITM_TYP_C" />
<property name="mdrm4Code" column="MDRM_C" />
<property name="itemSequence" formula="((MAX(MIC_CTL_SEQ_R) -1) * 220) + MAX(MIC_ITM_SEQ_R) - MAX(ITM_OCRN_R) + 1" />
<property name="occurrenceCount" formula="MAX(ITM_OCRN_R)" />
<many-to-one name="seriesDefinition">
<column name="ser_id_r" ></column>
<column name="efct_d"></column>
<column name="dist_c"></column>
</many-to-one>
</class>
</hibernate-mapping>


<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.acme">
<class name="SeriesDefinition" table="XRV_SER_DFN_CTL" >
<composite-id name="seriesDefinitionIdentity" class="com.acme.SeriesDefinitionIdentity">
<key-property name="seriesName" column="ser_id_r" />
<key-property name="effectiveDate" column="efct_d" />
<key-property name="districtCode" column="dist_c" />
<key-property name="seriesDefinitionStatusCode" column="ser_dfn_stat_c" />
</composite-id>
<set name="items" lazy="false">
<key unique="true" >
<column name="ser_id_r" ></column>
<column name="efct_d"></column>
<column name="dist_c"></column>
</key>
<one-to-many class="ItemDefinition" />
</set>



</class>
</hibernate-mapping>

Code between sessionFactory.openSession() and session.close():
SeriesDefinitionIdentity sdi = new SeriesDefinitionIdentity();
sdi.setSeriesName("FRY9LP");
sdi.setDistrictCode("02");
sdi.setEffectiveDate(new SimpleDate("20010331"));
sdi.setSeriesDefinitionStatusCode("P");

SeriesDefinition seriesDefinition = (SeriesDefinition)PersistenceEngineManager.getEngine("star").load(SeriesDefinition.class, sdi);

Full stack trace of any exception that occurs:
Foreign key (FK33F0F8465CA0D126:XRV_SER_DFN_ITMS [ser_id_r,efct_d,dist_c])) must have same number of columns as the referenced primary key (XRV_SER_DFN_CTL [ser_id_r,efct_d,dist_c,ser_dfn_stat_c])



Name and version of the database you are using: DB2


Debug level Hibernate log excerpt:

You have speicfied that an ItemDefinition's primary key has 4 columns:But you're looking it up using only three columns from in the set:You need to match up the columns better (using property-ref). Obviously the key in the set doesn't map exactly to the primary key (after all, it'd be a one-to-one if it did that). The easiest thing to do is to set up a <properties> tag in your ItemDefinition mapping, then refer to it using property-ref in the <key> element of the <set> element in SeriesDefinition.

Thank for your reply.

I am still having some difficulties with this. I can't put the foreign properties into a <properties> tag because it is already present as part of ItemDefinition's composite keys (the <properties> example in the documentation - 5.1.14 - conveniently shows its use with a single identity property).

Also, if I try have the SeriesDefinition set <key> (one-to-many) element use a property-ref, then it complains that it can't find it within SeriesDefinition.

Something needs to be done to match up your columns, or else you've got a many-to-many mapping. Does seriesDefinitionStatusCode have to be part of the SeriesDefinition's primary key? If it wasn't there, your mapping would work. Given that it is there, should ItemDefinition also have that value? If you've got two SeriesDefinitions with the same seriesName, effectiveDate and districtCode, but different seriesDefinitionStatusCodes, which one owns the ItemDefinition with the same seriesName, effectiveDate and districtCode? You must get that relationship sorted before hibernate can figure out what's going on.