带有联接的休眠查询：QuerySyntaxException：意外令牌

Question

I want to make a query using join , i tested it but i have this error

org.hibernate.hql.ast.QuerySyntaxException: unexpected token..

i did:

public List <Card>getCard(Client c) {
        ClientDAO cd = new ClientDAO();
        List<Card> ca = getSessionFactory().getCurrentSession().createQuery("select ca.column1,e.column2 from card ca join ens e on ca.ide=e.ide where ca.idclient="+ cd.getClient(c).getIdclient()).list();//this is a method to get the current client
        return ca;

Answer 1

You have used an SQL syntax to write a HQL query. In case the Card entity has an ens association, you would write a query like this:

List<Card> ca = getSessionFactory().getCurrentSession()
    .createQuery(
        "select ca " +
                "from Card ca " +
                "join fetch ca.ens " +
                "where ca.idclient = :idclient")
        .setParameter("idclient", cd.getClient(c).getIdclient())
        .list();
    return ca;
}

If you want an SQL query, since you have a projection, you would write a native query instead:

List<Object[]> ca = getSessionFactory().getCurrentSession()
    .createSQLQuery(
        "select ca.column1, e.column2 " +
        "from card ca " +
        "join ens e on ca.ide=e.ide " +
        "where ca.idclient = :idclient")
    .setParameter("idclient", cd.getClient(c).getIdclient())
.list();

In this case you get a List of Object[] . Each Object[] is associated to a selected row, and each array element is a column value.