擅长:python、mysql、java
<p>尝试以下操作:</p>
<pre><code>qa = session.query(ChildA)
qb = session.query(ChildB)
# @note: *qa* and *qb* may include other filters etc,
# but assuming they do not contain joins on *Parent*
subquery = qb.subquery()
qry = qa.join(Parent).join(subquery)
</code></pre>