db2 full-incremental-delta restore/recovery question

[Jimmy Chen]

Recently I've done a db2 backup and restore/recovery, but the process
for recovering the database was different than what I thought to be.

here is what I did:

DB2 is set in online mode

- backup -
* backup db2 in full
* insert record
* backup db2 in incremental
* insert record
* backup db2 in delta
* run command "archive log for db abc" and three log files archived to
tape

drop the database

- restore/recovery -
* restore delta backup - read from tape
* restore incremental backup - read from tape
* restore full backup - read from tape
* restore delta backup - read from tape

rollforwarding to end of log
5 log files applied and it was much fast than I thought, during
backup, there where at least 30 log files being created and archived
to tape. Most of them were in size of about 1 GB, but the archive log
applied was very small for roll forward.

what logs being applied (needed) and why the data (delta backup) being
read twice from tape? DB2 document no where tell the process in
detail, any one can help to explain?

Thanks,
Jimmy

[Pierre Saint-Jacques]

The reason the reason the delta backup is read twice is because it is the
most recent and therefore has the most recent values for the recovery
history.
The first read only gets the recovery history which is used to find A) the
most recent FULL from which to start and B) the intervening incremental full
or incremental deltas and C) the proper sequence in which to apply those.
AFAIK, the sequence should be in your case:
Incremental delta from tape - To get the sequence from history
Full image from tape
Full Incremental
Delta Inceremental - Again to get the last of your insert.
Roll Forward (If needed)
If you set your DIAGLEVEL to 4 in the dbm cfg, you will be able to get msgs.
which will indicate that flow.

As to your log files, I'm not sure I understand what you are saying. Abit
more detail in the mechanics might help.
HTH, Pierre.
"Jimmy Chen" <ji*********@hotmail.com> a écrit dans le message de
news:5e**************************@posting.google.c om...

Recently I've done a db2 backup and restore/recovery, but the process
for recovering the database was different than what I thought to be.

here is what I did:

DB2 is set in online mode

- backup -
* backup db2 in full
* insert record
* backup db2 in incremental
* insert record
* backup db2 in delta
* run command "archive log for db abc" and three log files archived to
tape

drop the database

- restore/recovery -
* restore delta backup - read from tape
* restore incremental backup - read from tape
* restore full backup - read from tape
* restore delta backup - read from tape

rollforwarding to end of log
5 log files applied and it was much fast than I thought, during
backup, there where at least 30 log files being created and archived
to tape. Most of them were in size of about 1 GB, but the archive log
applied was very small for roll forward.

what logs being applied (needed) and why the data (delta backup) being
read twice from tape? DB2 document no where tell the process in
detail, any one can help to explain?

Thanks,
Jimmy