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List:       jboss-user
Subject:    [JBoss-user] [EJB/JBoss] - Re: Foreign key set to NULL
From:       hbaxmann <nukes () jboss ! org>
Date:       2004-05-31 15:23:48
Message-ID: 9579226.1086017028471.JavaMail.roy () zeus
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It is a question of cardinality of the relationship _end_. Set a NOT NULL constraint \
on the FK will give you the exception. The full cardinality of the relation will then \
be: (Entity A)1:1 <--is a--> 1:1(Entity B) which means: "one and exactly one is A one \
and exactly one B" in contrast to "one or no A is one or no B": 0:1<--is a-->0:1.

JBoss has obviously in your case the 0 as default for the lower boundary of \
relationship ends. But this should come from the NOT NULL attribute of \
DatabaseMetadata.

bax

View the original post : \
http://www.jboss.org/index.html?module=bb&op=viewtopic&p=3836972#3836972

Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&p=3836972




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