Question

以下查询在SequelPro中执行时有效：

SELECT * FROM friend_computer LEFT JOIN computer m ON computer_id = m.id LEFT JOIN computer_status ms ON m.id = ms.computer_id JOIN friend_account pa ON friend_account_id = pa.id WHERE friend_account_id = 1 ORDER BY coalesce(ms.last_connect_time < ms.last_disconnect_time, -1) asc;

但是在Hibernate中，我不断收到以下语法错误：

String sql2 = "SELECT pm FROM FriendComputer pm LEFT JOIN FETCH pm.computer m JOIN FETCH pm.friendAccount pa " +
        "WHERE pm.friendAccount.id = :friendId AND pm.computer = m  ORDER BY coalesce((m.computerStatus.lastDisconnectTime < m.computerStatus.lastConnectTime),-1 ) " + sortOrder;
         org.hibernate.query.Query q = session().createQuery(sql2).setParameter("friendId", friendId);

语法错误是由于合并功能引起的。我找不到有关如何在合并中使用表达式的在线资源。

Answer 1

您想做什么？明确的case至少可以提供清晰的信息：

order by (case when ms.last_connect_time < ms.last_disconnect_time then 2
               when  ms.last_connect_time >= ms.last_disconnect_time 1
               else 0
          end)

与条件表达式合并

1 个答案: