What is partial backup? -- It is a backup when some Storage Areas are included and some are excluded from the backup.

One could not make a Partial online backup or Partial backup of a replication Target database with this method because the first step will be to truncate bi. Truncate bi could not be made on running database or one involved in replication as a target.

Here is an example on sports database. Let's assume I am not interested in Customers, Orders, Order-Lines and need to work with static tables only, tables like Item, Salesrep, State, Local-Default, Ref-Call. So I need to backup only area 7 "Info Area" and I would like to skip all other areas from area 8 to area 11.

1. Truncate bi

proutil sports -C truncate bi

2. Make a copy of .st file

cp sports.st sports.st.save

3. Remove areas that not needed for backup from .st file. Here is how my changed sports.st looks like

#
b /workdir/
#
d "Schema Area":6,64;1 /workdir/
#
d "Info Area":7,32;1 /workdir/

4. Build new .db file

rm sports.db
prostrct builddb sports

5. Make a backup

probkup sports /some_dir/sports.bkp

That backup will run much faster since we excluded areas 8 to 11

Now we need to assemble our database back to what it was.

6. Move original .st file back

mv sports.st.save sports.st

7. Then we need to fix time stamp for all extents that were not included in a backup.

dd if=sports_7.d1 of=sports_8.d1 bs=1024 count=1 skip=0 seek=0 conv=notrunc
dd if=sports_7.d1 of=sports_9.d1 bs=1024 count=1 skip=0 seek=0 conv=notrunc
dd if=sports_7.d1 of=sports_10.d1 bs=1024 count=1 skip=0 seek=0 conv=notrunc
dd if=sports_7.d1 of=sports_11.d1 bs=1024 count=1 skip=0 seek=0 conv=notrunc

8. Build the .db file again

rm sports.db
prostrct builddb sports

9. We assembled the original database back to what it was, so now we can start the database

proserve sports

10. The backup made in step 5 could be restored using structure in step 3. The "shortened" database will work for tables in this case with Area 7 tables only

for each salesrep:
 display salesrep.
end.
for each invoice:
 display invoice.
end.

But it will fail (and it should fail) for tables in other areas that were not included in a backup.

for each customer:
 display customer.
end.

SYSTEM ERROR: Attempt to read block 12 which does not exist in area 9, database /some_dir2/sports. (210) (14684)

We do not have areas 8 to 11 so that is not a surprise that customer query errors out.

I would not do that Partial Backup on a mission-critical database without a test or two.

P.S. I would prefer if PSC makes a documented method of making a Progress Partial Backup rather then changing bytes and bits as it is described above.