我們需要通過發送器獲取最後發佈的消息組。JAVA Persistence OrderBy在GroupBy之前
Query query = em.createQuery("SELECT m FROM Message m " + "JOIN m.transmitter " + "JOIN m.recipient " + "WHERE m.transmitter = :u1 " + "OR m.recipient = :u1 " + "GROUP BY m.recipient,m.transmitter " + "ORDER BY m.sendDate DESC"); query.setParameter("u1", actualUser);
,但我們需要的是這樣的,我們得到了最早的消息:
Query query = em.createQuery("SELECT m FROM Message m " + "JOIN m.transmitter " + "JOIN m.recipient " + "WHERE m.transmitter = :u1 " + "OR m.recipient = :u1 " + "ORDER BY m.sendDate DESC" "GROUP BY m.recipient,m.transmitter "); query.setParameter("u1", actualUser);
感謝您的幫助對不起我的英語。
不是真的和JPQL不接受子查詢。 – 2014-12-05 15:53:38