Question

我有一个类Transaction。交易有发件人。发件人有一个字段＆＃39; test＆＃39;。 transaction.sender可以为null。

我尝试获取发件人= null或sender.test = true的所有交易

我在HQL中试过

select * from Transaction t where ((t.sender is null) or (t.sender.test is true))
select * from Transaction t where ((t.sender is null) or (t.sender.test in (true)))
select * from Transaction t where ((t.sender is null) or (t.sender.test = true))

并且我只获得了与＆＃39; t.sender.test的交易是真的，我没有得到＆t; t。“的交易是空的＆＃39 ;

如果我只尝试：

select * from Transaction t where t.sender is null

我得到的交易＆＃39; t.sender为空＆＃39;

任何人都可以帮助我吗？

谢谢

编辑：我的代码是

StringBuilder q = new StringBuilder("from Transaction t where MONTH(t.dateTransfered) = :month and YEAR(t.dateTransfered) = :year ");
if (Val.required(request.getParameter("test"))){
        test = Boolean.valueOf(request.getParameter("test"));
        if (test){
            q.append("and ((t.sender is null) or (t.sender.test = true))");
        }
}

编辑2：

public List<Transaction> get(HttpServletRequest request, Date date, int start, int end) {

    StringBuilder q = new StringBuilder("from Transaction t where MONTH(t.dateTransfered) = :month and YEAR(t.dateTransfered) = :year ");

    if (Val.required(request.getParameter("niv")))
        q.append("and (t.sender.id = :niv or t.receiver.id = :niv) ");

    if (Val.required(request.getParameter("status")))
        q.append("and t.transactionStatus = :status ");

    if (Val.required(request.getParameter("serviceType")))
        q.append("and transactionServiceType = :serviceType ");

    if (Val.required(request.getParameter("source"))) {

        q.append("and transactionSource = :source ");

        if (Val.required(request.getParameter("sourceMethod"))) {
            q.append("and transactionSourceMethod = :sourceMethod ");
        }
    }

    boolean test = false;

    if (Val.required(request.getParameter("test"))){
        test = Boolean.valueOf(request.getParameter("test"));
        if (test){
            q.append("and ((t.sender is null) or (t.sender.test = true))");
        }
        else{
            q.append("and (t.sender.test = false and t.receiver.test = false)");
        }
    }
    else {
        q.append("and (t.sender.test = false and t.receiver.test = false)");
    }

    Query qry = entityManager.createQuery(q + " order by t.dateTransfered desc");

    qry.setParameter("month", DateUtil.getRealMonth(date));
    qry.setParameter("year", DateUtil.getYear(date));

    if (Val.required(request.getParameter("niv")))
        qry.setParameter("niv", Long.valueOf(request.getParameter("niv")));

    if (Val.required(request.getParameter("status")))
        qry.setParameter("status", TransactionStatus.valueOf(request.getParameter("status")));

    if (Val.required(request.getParameter("serviceType")))
        qry.setParameter("serviceType", TransactionServiceType.valueOf(request.getParameter("serviceType")));

    if (Val.required(request.getParameter("source"))) {

        qry.setParameter("source", TransactionSource.valueOf(request.getParameter("source")));

        if (Val.required(request.getParameter("sourceMethod"))) {
            qry.setParameter("sourceMethod", request.getParameter("sourceMethod"));
        }
    }




    qry.setFirstResult(start).setMaxResults(end);

    try {
        return (List<Transaction>) qry.getResultList();
    } catch (NoResultException e) {
        return null;
    } catch (Exception e) {
        e.printStackTrace();
        return null;
    }
}

Answer 1

t.sender.test与发件人创建隐式内部联接。你需要的是左连接。 select *，BTW，是SQL，而不是HQL。你想要的是

select t from Transaction t 
left join t.sender s
where s.id is null or s.test = true

选择具有可能NULL值的HQL

1 个答案: