Hello,

this i have to map:

<!-- Medium -->
<!-- Zu mappende Attribute: erscheinungsjahr, medienart, preis, signatur, titel -->
<entity class="Medium" access="FIELD">
<!-- Vererbung liegt vor: -->
<inheritance/>
<discriminator-column name="MARTID" />

<attributes>
<id name="signatur">
<column name="SIGNATUR" />
<!-- Automatische Erzeugung von Schlüsselwerten -->
<generated-value strategy="AUTO" />
</id>
<basic name="titel">
<column name="TITEL" />
</basic>
<basic name="erscheinungsjahr">
<column name="ERSCHEINUNGSJAHR" />
</basic>
<basic name="preis">
<column name="WIEDERBESCHAFFUNGSPREIS" />
</basic>
<many-to-one name="medienart" fetch="LAZY">
<join-column name="MARTID" />
</many-to-one>
</attributes>
</entity>

<!-- Buch -->
<!-- Zu mappende Attribute: isbn -->
<entity class="Buch" access="FIELD">
<discriminator-value>1</discriminator-value>
<attributes>
<basic name="isbn" optional="false">
<column name="ISBN" />
</basic>
</attributes>
</entity>

<!-- Zeitschrift -->
<!-- Zu mappende Attribute: issn -->
<entity class="Zeitschrift">
<discriminator-value>2</discriminator-value>
<attributes>
<basic name="issn" optional="false">
<column name="ISSN" />
</basic>
</attributes>
</entity>

But now I get the error: Caused by: org.hibernate.MappingException: Repeated column in mapping for entity: Buch column: MARTID (should be mapped with insert="false" update="false"). But haven't I to set MARTID twice? First to say what make out Buch and Zeitschrift and secound to get medienart (?).

Why is it wrong?

Greetings Matthias