Database 为什么更新没有看到子查询的结果？[甲骨文]

此查询更新0行后：

UPDATE F_ANSWER fa 
SET fa.STATUS_ID = 5 
WHERE fa.ANSWER_ID IN (SELECT FA1.ANSWER_ID 
                       FROM F_ANSWER FA1 
                       WHERE FA1.ANSWER_ID = (SELECT ANSWER_ID 
                                              FROM F_ANSWER FA2 
                                              WHERE FA2.QUERY_ID = FA1.QUERY_ID 
                                              ORDER BY ANSWER_ID DESC 
                                              FETCH FIRST ROW ONLY) 
);

但单独选择返回的2行ID为：

SELECT FA1.ANSWER_ID 
FROM F_ANSWER FA1 
WHERE FA1.ANSWER_ID = (SELECT ANSWER_ID FROM F_ANSWER FA2 

为什么呢

没有从子查询到查询的链接的简化子查询工作正常：

UPDATE F_ANSWER fa 
SET fa.STATUS_ID = 5 
WHERE fa.ANSWER_ID IN (SELECT FA1.ANSWER_ID 
                       FROM F_ANSWER FA1 
                       WHERE FA1.ANSWER_ID = (SELECT ANSWER_ID 
                                              FROM F_ANSWER FA2 
                                              ORDER BY ANSWER_ID DESC 
                                              FETCH FIRST ROW ONLY) 
);

我可以通过两个查询来解决我的问题-1个用于选择必要的ID，2个用于更新

---

但有意思的是，为什么update无法看到具有这种结构的子查询的结果。

您编写了两个不同的update查询选项：（1）一个使用相关子查询编写，另一个（2）仅使用子查询编写

我相信，您的数据是upd查询（1）中的谓词

切断数据

在主更新查询中，此块是相关子查询

在这个查询中，您使用的是一个子查询，而不按查询ID进行关联( .... 其中FA2.QUERY\u ID=FA1.QUERY\u ID .... ):

您可以提供数据示例并制定任务。

---

您的UPD查询可以更轻松地重写。

请解释！

         WHERE FA1.ANSWER_ID = (SELECT ANSWER_ID 
                          FROM F_ANSWER FA2 
                          WHERE FA2.QUERY_ID = 
                          FA1.QUERY_ID
                          ORDER BY ANSWER_ID DESC 
                          FETCH FIRST ROW ONLY)

    UPDATE F_ANSWER fa 
    SET fa.STATUS_ID = 5 
    WHERE fa.ANSWER_ID IN (SELECT FA1.ANSWER_ID 
                           FROM F_ANSWER FA1 
                           WHERE FA1.ANSWER_ID = (SELECT ANSWER_ID 
                                                  FROM F_ANSWER FA2 
                                                  WHERE FA2.QUERY_ID = 
                                                        FA1.QUERY_ID
                                                  ORDER BY ANSWER_ID DESC 
                                                  FETCH FIRST ROW ONLY)
    );

    UPDATE F_ANSWER fa 
    SET fa.STATUS_ID = 5 
    WHERE fa.ANSWER_ID IN (SELECT FA1.ANSWER_ID 
                           FROM F_ANSWER FA1 
                           WHERE FA1.ANSWER_ID = (SELECT ANSWER_ID 
                                              FROM F_ANSWER FA2 
                                              ORDER BY ANSWER_ID DESC 
                                              FETCH FIRST ROW ONLY)
    );