一、前言

這個東西，難度幾乎沒有，就是繁瑣。

一條簡單的select count（*） from table_name

都能有多種書寫方式。

總是忘，這裡記錄下。

一 、通過Criteria 查詢

        Criteria criteriaCount = getCriteria();
        criteriaCount = criteriaCount.add(Restrictions.eq("dispatchTaskId", dispatchTaskId));
        criteriaCount.setProjection(Projections.rowCount());
        Integer totalCount 
 
= ((Long) criteriaCount.uniqueResult()).intValue();

二、通過原生sql查詢

        SQLQuery queryCount = getSession().createSQLQuery("SELECT COUNT(*) FROM incidentInformation  WHERE ii.incidentInformationId = :incidentInformationId AND dti.taskstate = :taskstate");

        queryCount.setParameter(
 
"incidentInformationId", incidentInformationId);
        queryCount.setParameter("taskstate", ETaskStatus.STATUS_INIT.getStatusValue());
        int count = ((BigDecimal) queryCount.uniqueResult()).intValue();

        return count;

三、通過hibernate的查詢語言查詢

        String countHql = "select count(*) from  a  where and a.approveResult = :approveResult and a.approverId = :approverId";
        Query countQuery 
 
= getSession().createQuery(countHql);
        countQuery.setParameter("approverId", approverId);
        int count = ((Long) countQuery.uniqueResult()).intValue();