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Hi Guys,<br>
<br>
I found the ugliest, weirdest persistance bug ever, I think. Ok. It
happens in the context of a one-to-one composition that is navigable in
both ways.<br>
<br>
Example, take the Motion concept (a proposal at a company's shareholder
meeting). Sometimes, you need to attach to a Motion instance, a
MotionAnalysis. So there is a one-to-one composition from Motion to
MotionAnalysis called "analysis&lt;--&gt;motion", that is navigable in
both ways.<br>
<br>
Ok, I admit that it might not be the very best model pattern, but hey,
sometimes the model grows hairy without some of the hairiness being
noticed.<br>
<br>
So first, anyways when you have this, first, in the SQL table
structure, you have a, in the MOTION table, a MOTION_ANALYSIS_FK <b>and</b>,
in the MOTION_ANALYSIS table, you also get a MOTION_FK. When, of
course, only one of the foreign key reference is necessary. This is the
first part of the bug.<br>
<br>
Also, when you create a MotionAnalysis insance from the a Motion
instance, Hibernate sets the MOTION.MOTION_ANALYSIS_FK field, but
leaves the MOTION_ANALYSIS.MOTION_FK in a null state. This seems to
explain the following behavior, which is the visible tip of the bug...
When you retrieve an instance from the MotionAnalysis "side"&nbsp; :<br>
<pre>FROM
	MotionAnalysis AS ma
WHERE
	ma.published &lt;= current_date()
	AND ma.published &gt;= :startDate
ORDER BY
	ma.published DESC
</pre>
the MotionAnalysis.motion is always null (ma.motion is null), which is
impossible because it is a composition.<br>
<br>
But, when you get it from the Motion "side" : <br>
<pre>FROM
	Motion AS mo
	JOIN mo.analysis AS ma
WHERE
	ma.id IS NOT null
	AND ma.published &lt;= current_date()
	AND ma.published &gt;= :startDate
	AND mo.meeting.enterprise.country.id IN (SELECT country.id FROM Client client INNER JOIN client.analysisCountries AS country WHERE client.id = :clientId)
ORDER BY
	ma.published DESC

</pre>
, everything is fine... That is, the association is set correctly, etc.
The worst thing is that this was working only some weeks ago, as I
tested it myself...<br>
<br>
<br>
Vincent<br>
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