depends on the OS, the OS timestamps are meaningless and not used by Oracle.

some OS's update timestamps only when files are closed, datafiles are not closed all that often.

and that is one that doesn't do timestamps like normal OS's. Ignore it, we do - we don't use them.

export and expdp are NOT BACKUP tools, they are data copy tools, they are NOT BACKUPS.


full backup: http://docs.oracle.com/docs/cd/B10501_01/server.920/a96519/glossary.htm#432659

as stated there, a full backup does not refer to "how much" but rather "how" a single file is backed up.

Now, in general, many people (self included) think of a full backup as:

a) control file backup
b) plus datafile backup
c) plus any archives needed to restore and recover b with
d) parameter file backup

you never never never backup online redo logs. never.



b) a cold backup by definition means the database is cold, stopped, not hot, cold. You ALWAYS stop the database before a cold backup by definition.

c) because that is what the word 'hot' means - that the database is in fact 'hot', up, running, doing stuff, not cold.

d) hot, only - if you ask me.


archives: you need to keep all archives that were generated during/after all of your backups. You can release these archives (remove them from tape, disk, whatever) AFTER you remove the backups they are needed to be applied to (because you keep AT LEAST your least two or three backups).

You backup these archives ASAP - and get them mirrored on another set of disks elsewhere or on tape elsewhere. They are crucial for recovery. Just as you do not keep your backup on the production machine (because if the production machine burns up in a fire....) you do not want to keep your archives there long either.

1) neither is - they are both point in time things. You will LOSE data with either approach.

exports are not backups, backups are backups. You would be wise to NOT use export and think of it as a backup - it isn't. There is a high probability you cannot import those exports - have you ever tried?

(most common error - people using "consistent=Y" when exporting using SYS or SYSDBA. Neither of them can do consistent exports - ever.

2) for cold backup - you can copy however you like, we don't care, we are not even running. copy would maintain the format of the original file - there is nothing special there for a cold backup. It would only be during a hot backup that you would have to think about this - since windows won't let you copy a file that is opened by someone else.




Actually , what you should be thinking about is how to get these databases into archive log mode. It is only a matter of time before you suffer a severe data loss. Just a matter of time.

export is not backup.

backup is backup.

period. export is a tool you can use to make a logical copy of your database - it is not a backup



they will both lose data - at the same rate. export might lose everything because there is never a guarantee you can import it later.