delete OBSOLETE 與 delete expiried

delete obolete 不能加從句嗎？
還是delete obolete 只是針對備份集？

delete obolete copy;
delete obsolete backup;
這兩個都不行，而下面的可以：

delete expired copy;
delete expired backup;

先弄懂這兩個expired  obolete區別：
expired 標示 備份被手工刪除或損壞。
obolete 是指備份過期了。
delete obolete 不能加從句
delete obolete 針對過期 的備份集和副本。

You can automatically delete obsolete backups and copies by issuing the DELETE OBSOLETE command. For example, you can enter:
# delete obsolete backups and copies displayed when you issue REPORT OBSOLETE
DELETE OBSOLETE;
# delete obsolete backups and copies according to a specified recovery window
DELETE OBSOLETE RECOVERY WINDOW OF 7 DAYS;
# delete obsolete backups and copies according to a specified redundancy
DELETE OBSOLETE REDUNDANCY = 2;