具有公用表表达式的删除查询（“ WITH AS”子句）

Question

我正在尝试从oracle数据表中删除41.6％的旧行（senstrig是日期格式）：

DELETE FROM
    (WITH RS AS (SELECT * FROM OLD_WIFISIGN WHERE SENSID= 1 ORDER BY SENSTRIG ASC))
WHERE ROWNUM <= (SELECT COUNT (*)/ 2.4 FROM RS);

但返回错误：

ORA-00928缺少SELECT

我已经尝试过多个版本，但是没有运气。

您能帮我怎样使这个“删除自”运行中？

Answer 1

将WITH放在DELETE之前：

WITH RS AS (SELECT * FROM OLD_WIFISIGN WHERE SENSID= 1 ORDER BY SENSTRIG ASC)
DELETE FROM OLD_WIFISIGN 
WHERE ROWNUM <= (SELECT COUNT (*)/ 2.4 FROM RS);

还是有点奇怪，命令的目的是什么？