PL / SQL：删除游标内的行不起作用

Question

如何从PL / SQL游标循环中的表中删除行？猜猜，我对这段代码做错了什么：

DECLARE
  CURSOR myCursor IS SELECT * FROM A WHERE <some-condition> FOR UPDATE;
BEGIN
  FOR x IN myCursor LOOP
    DELETE FROM A WHERE CURRENT OF myCursor;
  END LOOP;
END;

如果我用DELETE替换UPDATE语句，一切都按预期工作（除此之外，记录只会更新而不是删除）。例如：

DECLARE
  CURSOR myCursor IS SELECT * FROM A WHERE <some-condition> FOR UPDATE;
BEGIN
  FOR x IN myCursor LOOP
    UPDATE A SET FOO = 'bar' WHERE CURRENT OF myCursor;
  END LOOP;
END;