将总和和算术结果用作休眠条件中的顺序键

Question

如何用hibernate条件表达此查询。

SELECT anId, SUM(fieldA) AS A, SUM(fieldB) AS B, SUM(fieldA)+SUM(fieldB) AS 'total' FROM tableA GROUP BY anId ORDER BY 'total' DESC LIMIT 5

Answer 1

符合以下条件的技巧

        Criteria criteria = hibernateSession
                .createCriteria(YourEntity.class);
        criteria.setProjection(Projections
                .projectionList()
                .add(Projections.property("anId").as("prop1"))
                .add(Projections.sum("fieldA").as("prop2"))
                .add(Projections.sum("fieldB").as("prop3"))
                .add(Projections.sqlProjection(
                        "sum(fieldA) + sum(fieldB) as total",
                        new String[] { "total" },
                        new Type[] { StandardBasicTypes.INTEGER }), "total")
                .add(Projections.groupProperty("remarks")));
        criteria.addOrder(Order.desc("total"));
        criteria.setMaxResults(5);
        criteria.setResultTransformer(Transformers.ALIAS_TO_ENTITY_MAP);
        List list = criteria.list();
        for (Object object : list) {
            Map<Object, Object> map = (Map<Object, Object>) object;
            System.out.println(map);
        }