hibernate

-- select  後面沒有加別名

Encountered a duplicated sql alias [id] during auto-discovery of a native-sql query

-- 看看數據庫是否沒有這個column

could not extract ResultSet

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session.createQuery(queryStr).list();　　//hql
session.createSQLQuery(queryStr).list();　　//普通sql

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hibernate 左鏈接：

@Test
    public void testLetfJion() {
        Session session = sessionFactory.getCurrentSession();
        session.beginTransaction();
        String queryStr = "select stu from com.bjsxt.hibernate.Student as stu left join com.bjsxt.hibernate.Teacher as te on stu.id = te.id";
        session.createQuery(queryStr).list();
        session.getTransaction().commit();
    }

報錯：java.lang.IllegalStateException: DOT node with no left-hand-side!

正確寫法：

    @Test
    public void testLetfJion() {
        Session session = sessionFactory.getCurrentSession();
        session.beginTransaction();
        String queryStr = "select stu from com.bjsxt.hibernate.Student as stu ,com.bjsxt.hibernate.Teacher as te where stu.id = te.id";
        session.createQuery(queryStr).list();
        session.getTransaction().commit();
    }

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IN適合於外表大而內表小的狀況；EXISTS適合於外表小而內表大的狀況。