使用 rownum 时选择子选择（Java Hibernate Persistence）答案

【问题标题】：select with sub select when using rownum(Java Hibernate Persistence)使用 rownum 时选择子选择（Java Hibernate Persistence）
【发布时间】：2016-06-01 05:29:56
【问题描述】：

在我的代码中，我有这个带有标准投影列表的通用休眠查询来列出选择字段并设置第一个/最大结果以限制行数。

private Criteria getCriteria(Status status, Class<?> T, String aliasName, String subTable, String subAlias, List<Criterion> criterionList, List<Order> orderList, ProjectionList projectionList, Integer firstResult, Integer maxResult, Session session) {
    StringBuilder methodFullNameSb = new StringBuilder("Criteria: getCriteria(Status, Class<?>, String, String, String, List<Criterion>, List<Order>, ProjectionList,Integer, Integer)");
    MethodLevelLogger methodLevelLogger = MethodLevelLogger.getCurrentInstance(methodFullNameSb.toString());
    methodLevelLogger.start();

    Criteria criteria = null;
    try {
        criteria = session.createCriteria(T, aliasName);
        if (subAlias != null && !subAlias.isEmpty()) {
            criteria.createAlias(subTable, subAlias).setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY).setReadOnly(true);
        }

        if (criterionList != null) {
            for (Criterion criterion : criterionList) {
                criteria.add(criterion);
            }
        }

        if (orderList != null) {
            for (Order order : orderList) {
                criteria.addOrder(order);
            }
        }

        //to setlect field
        if (projectionList != null) {
            criteria.setProjection(projectionList);
        }

        //to limit row number
        if (firstResult != null && maxResult != null) {
            criteria.setFirstResult(firstResult);
            criteria.setMaxResults(maxResult);
        }
        // Set Cache MODE DISABLE
        criteria.setCacheMode(CacheMode.IGNORE).setReadOnly(true);

    } catch (HibernateException | NullPointerException e) {
        ApplicationExceptionHandle.doApplicationExceptionHandleAPP001withStackTrace(status, e, log);
    } catch (Exception exception) {
        ApplicationExceptionHandle.doApplicationExceptionHandleAPP001withStackTrace(status, exception, log);
    }

    methodLevelLogger.end();
    log.debug(methodLevelLogger.getMessageTimeDiff());
    return criteria;
}

但是，没有限制行数，每件事看起来都很好，如 SQL 日志所示。

 2016-05-31 16:49:41,769 INFO  [stdout]:71 - Hibernate: 
 2016-05-31 16:49:41,769 INFO  [stdout]:71 -     /* criteria query */ select
 2016-05-31 16:49:41,769 INFO  [stdout]:71 -         /*+index(this_     ORDHIS_IDX)*/ this_.ORDER_HISTORY_ID as H_ORDER_HISTORY_ID,
 2016-05-31 16:49:41,769 INFO  [stdout]:71 -         this_.ORDER_TRAN_ID as y1_,
 2016-05-31 16:49:41,769 INFO  [stdout]:71 -         this_.UUID as y2_,
 2016-05-31 16:49:41,769 INFO  [stdout]:71 -         this_.MOBILE_NO as y3_,
 2016-05-31 16:49:41,769 INFO  [stdout]:71 -         this_.MOBILE_SEGMENT as y4_,...
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -     from
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         suiadm.SSC_ORDER_HISTORY this_,
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         suiadm.SSC_ORDER_ITEM orderitems1_ 
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -     where
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         this_.ORDER_HISTORY_ID=orderitems1_.ORDER_HISTORY_ID 
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         and this_.CREATE_BY=? 
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         and this_.SFF_STATUS in (
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -             ?, ?, ?, ?
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         ) 
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         and this_.MOBILE_SEGMENT in (
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -             ?, ?
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         ) 
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         and this_.CREATE_DATE between ? and ? 
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         and orderitems1_.EFF_CODE in (
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -             ?, ?
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         ) 
 2016-05-31 16:49:41,779 INFO  [stdout]:71 -         and this_.SERVICE_TYPE=?

无论如何，当我限制行数时，SQL如下

  2016-05-31 17:00:46,561 INFO  [stdout]:71 - Hibernate: 
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -     select
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -         * 
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -     from
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -         ( /* criteria query */ select
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -             /*+index(this_ ORDHIS_IDX)*/ this_.ORDER_HISTORY_ID as H_ORDER_HISTORY_ID,
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -             this_.ORDER_TRAN_ID as y1_,
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -             this_.UUID as y2_,
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -             this_.MOBILE_NO as y3_,
  2016-05-31 17:00:46,561 INFO  [stdout]:71 -             this_.MOBILE_SEGMENT as y4_,.....
  2016-05-31 17:00:46,579 INFO  [stdout]:71 -         from
  2016-05-31 17:00:46,580 INFO  [stdout]:71 -             suiadm.SSC_ORDER_HISTORY this_,
  2016-05-31 17:00:46,580 INFO  [stdout]:71 -             suiadm.SSC_ORDER_ITEM orderitems1_ 
  2016-05-31 17:00:46,580 INFO  [stdout]:71 -         where
  2016-05-31 17:00:46,580 INFO  [stdout]:71 -             this_.ORDER_HISTORY_ID=orderitems1_.ORDER_HISTORY_ID 
  2016-05-31 17:00:46,580 INFO  [stdout]:71 -             and this_.MOBILE_NO=? 
  2016-05-31 17:00:46,581 INFO  [stdout]:71 -             and this_.SFF_STATUS in (
  2016-05-31 17:00:46,582 INFO  [stdout]:71 -                 ?, ?, ?, ?
  2016-05-31 17:00:46,582 INFO  [stdout]:71 -             ) 
  2016-05-31 17:00:46,582 INFO  [stdout]:71 -             and this_.MOBILE_SEGMENT in (
  2016-05-31 17:00:46,582 INFO  [stdout]:71 -                 ?, ?
  2016-05-31 17:00:46,583 INFO  [stdout]:71 -             ) 
  2016-05-31 17:00:46,583 INFO  [stdout]:71 -             and this_.CREATE_DATE between ? and ? 
  2016-05-31 17:00:46,583 INFO  [stdout]:71 -             and orderitems1_.EFF_CODE in (
  2016-05-31 17:00:46,583 INFO  [stdout]:71 -                 ?, ?
  2016-05-31 17:00:46,583 INFO  [stdout]:71 -             ) 
  2016-05-31 17:00:46,583 INFO  [stdout]:71 -             and this_.SERVICE_TYPE=? ) 
  2016-05-31 17:00:46,584 INFO  [stdout]:71 -     where
  2016-05-31 17:00:46,584 INFO  [stdout]:71 -         rownum <= ?

代替

   select ... from ... where criteria1 and criteria2 and rownum < ?

我得到了子选择的选择

   select ... from select ... from where creiterai1 and criteria2 where rownum < ?

这在休眠状态下正常吗？还是我做错了什么？如果我愿意

  select ... from ... where criteria1 and criteria2 and rownum < ?

如何编辑我的代码？

【问题讨论】：

标签： hibernate

【解决方案1】：

这是使用 oracle 获取结果集第一页的通用方法。

它相当于你期望 hibernate 产生的查询。

请注意，当您对查询应用分页时，您应该对整个结果集进行排序，否则每次运行查询时可能会得到不同的结果。

order by 子句将放在生成的子选择休眠中（您对完整的结果集进行排序，然后限制到它的一页）：

 select
     * 
 from
     ( /* criteria query */ select
         /*+index(this_ ORDHIS_IDX)*/ this_.ORDER_HISTORY_ID as H_ORDER_HISTORY_ID,
         this_.ORDER_TRAN_ID as y1_,
         this_.UUID as y2_,
         this_.MOBILE_NO as y3_,
         this_.MOBILE_SEGMENT as y4_,.....
     from
         suiadm.SSC_ORDER_HISTORY this_,
         suiadm.SSC_ORDER_ITEM orderitems1_ 
     where
         this_.ORDER_HISTORY_ID=orderitems1_.ORDER_HISTORY_ID 
         and this_.MOBILE_NO=? 
         and this_.SFF_STATUS in (
             ?, ?, ?, ?
         ) 
         and this_.MOBILE_SEGMENT in (
             ?, ?
         ) 
         and this_.CREATE_DATE between ? and ? 
         and orderitems1_.EFF_CODE in (
             ?, ?
         ) 
         and this_.SERVICE_TYPE=? 
     **order by ...**
 ) 
 where
     rownum <= ?

【讨论】：

谢谢蒂埃里。