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From: Cecil Westerhof <Cecil@decebal.nl>
Newsgroups: comp.lang.java.programmer
Subject: A few JPQL questions
Date: Wed, 03 Feb 2016 08:46:52 +0100
Organization: Decebal Computing
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I do not have very much experience with JPA and especially with JPQL.
Yesterday shortly before leaving my colleague told me that he could
not use an embedded key in JPQL. He told me that when he used
something like:
    a.id = b.id
he got more records as when he used:
    a.id.first = b.id.first AND a.id.second = b.id.second …

I had not the time to evaluate this, but it seems very strange to me.
Could this be true? If so, what would be the reason? Otherwise, which
mistake has he likely made?

He also told me it was not possible to do a JOIN on a sub-query in
JPQL. He said it is only possible to use WHERE and HAVING. I assume he
made a mistake. What is most likely he did wrong?

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof