OFFLINE DROP is what you do to drop a datafile from a database
that is in no-archivelog mode. To completely remove it from the
data dictionary you must also drop the tablespace.
From the fine manual:
If the database is in NOARCHIVELOG mode, you must specify the DROP
clause to take a datafile offline. However, the DROP clause does not
remove the datafile from the database. To do that, you must drop the
tablespace in which the datafile resides. Until you do so, the
datafile remains in the data dictionary with the status RECOVER or
If the database is in ARCHIVELOG mode, Oracle ignores the DROP keyword.
On Mon, 27 Dec 2004 06:08:10 -0800 (PST), Joe Cooper
> I'm away from my office this week, and currently (conveniently?) away from my VPN access, so this response is strictly from memory. However, if memory serves me correctly, the difference is that on *NIX systems, 'offline drop' not only makes the datafile unavailable to the Oracle instance, it removes the datafile from the O/S (freeing the disk space for other uses). Thus, if you use the 'drop' option and don't have adequate backups elsewhere, you'd have a hard time recovering the file. As you have clearly demonstrated, it appears to make no difference on Windows systems.
> Of course, this is from memory, so any corroboration (or opposing view) is welcome.
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