Sorry for the late answer.
It works now thanks to you, Allistair.
I needed to use your "uid" field, common to the two entities but built
in different ways.
here is the result in a sample of the data-config.xml file
...
<document>
<entity name="newsfeeds" query="select id as nf_id, 'newsfeed ' ||
cast(id as char(50)) as nf_uid, text as nf_text, url, note from newsfeeds" >
<field column="nf_id" name="news_id" />
<field column="nf_uid" name="uid" />
...
</entity>
<entity name="messages" query="select id as m_id, 'message ' || cast(id
as char(50)) as m_uid, body from messages" >
<field column="m_id" name="message_id" />
<field column="m_uid" name="uid" />
...
</entity>
</document>
...
uid is define as uniqueKey in the schema.xml file.
Thank you for your help
