在oracle11g中插入行后发生回退的奇怪错误

Question

编写脚本来测试（待编写）触发器，但是如果回滚更改，则会收到一条奇怪的错误消息。 这是测试脚本

    insert into prescription values(
  143, 115, 
  to_date('January 15, 1989, 11:00 A.M.',
  'Month dd, YYYY, HH:MI A.M.',
  'NLS_DATE_LANGUAGE = American'),
  5, 12, 'hours', 12);
select * from prescription;
rollback;

在select语句返回的行中滚动大约一半后，表蒸发，并且出现错误消息：

ORA-01002: fetch out of sequence
01002. 00000 -  "fetch out of sequence"
*Cause:    This error means that a fetch has been attempted from a cursor
           which is no longer valid.  Note that a PL/SQL cursor loop
           implicitly does fetches, and thus may also cause this error.
           There are a number of possible causes for this error, including:
           1) Fetching from a cursor after the last row has been retrieved
           and the ORA-1403 error returned.
           2) If the cursor has been opened with the FOR UPDATE clause,
           fetching after a COMMIT has been issued will return the error.
           3) Rebinding any placeholders in the SQL statement, then issuing
           a fetch before reexecuting the statement.
*Action:   1) Do not issue a fetch statement after the last row has been
           retrieved - there are no more rows to fetch.
           2) Do not issue a COMMIT inside a fetch loop for a cursor
           that has been opened FOR UPDATE.
           3) Reexecute the statement after rebinding, then attempt to
           fetch again.

如果我在没有回滚的情况下运行脚本，然后分别发出回滚，则一切正常。 但这将使以后的测试单元变得烦人。

Answer 1

发现问题了！ 事实证明，默认情况下oracle SQL开发人员一次仅返回50行。 因此，当我开始向下滚动时，它将关闭并获取接下来的50行，这可能导致无效的结果，因为选择是在回滚之前发出的，并且出现错误。 通过进入preference-> database并更改返回大小来解决，幸运的是，对我来说，返回大小刚好在它们允许的最大数量之内（200个结果）。