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copied!<p>Having done some googling, it appears that this this is not possible - Hibernate only allows inclusion of the root entity alias using <code>{alias}</code> in the SQL string of the <code>SQLProjection</code>. I did however find <a href="https://hibernate.atlassian.net/browse/HHH-2952" rel="nofollow noreferrer">this issue regarding the limitation</a> on the Hibernate JIRA pages.</p> <p>Someone has kindly submitted a patch that allows the use of non-root aliases in the <code>SQLProjection</code> string, through a new <code>RestrictionsExt</code> class. Using my example from the question:</p> <pre><code>Projections.sqlProjection("MIN(i.powerRestarts) as value", new String[]{"value"}, new Type[]{new LongType()})) </code></pre> <p>The alias <code>i</code> can now be referenced as:</p> <pre><code>RestrictionsExt.sqlProjection("MIN({i}.powerRestarts) as value", "value", new LongType()) </code></pre> <p>I had to modify the static <code>RestrictionsExt.sqlProjection</code> method to allow specification of the type for the column alias (<code>"value"</code>) (here defined as <code>LongType</code>), as the patch didn't allow this and defaulted to <code>StringType</code>.</p> <p>The SQLAliasedProjection class in the patch also requires access to the following private methods in <code>org.hibernate.loader.criteria.CriteriaQueryTranslator</code>: <code>getOuterQueryTranslator</code> and <code>getAliasedCriteria</code>. To get this to work without modifying the Hibernate source, I used reflection:</p> <pre><code>cri = ((org.hibernate.loader.criteria.CriteriaQueryTranslator) criteriaQuery).getAliasedCriteria(alias); </code></pre> <p>was changed to:</p> <pre><code>Method m = ((org.hibernate.loader.criteria.CriteriaQueryTranslator) criteriaQuery).getClass().getDeclaredMethod("getAliasedCriteria", String.class); m.setAccessible(true); cri = (Criteria) m.invoke(((org.hibernate.loader.criteria.CriteriaQueryTranslator) criteriaQuery), alias); </code></pre> <p>Hopefully this will help anyone else facing the same problem.</p>

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