Save Option 21 and Access Paths (was SYSSAV & Access Paths)

[Al Barsa <barsa@xxxxxxxxxxxxxxxxxxx>]

Hi,

As I discovered the hard way, ACCPTH(*YES) becomes ACCPTH(*MAYBE) in V5R2.

I spoke with a database developer, who asked me why this wasn't better, and
I had to admit that it was better, although unexpected.

Here's the bottom line.  If a member has no records in it, it's faster to
rebuild the access path than restore it.  Furthermore, it's also faster to
not save the empty access path, *AND you save tape.

The only disadvantage are:

1.    You expect to see the access paths saved to tape, and you don't.
2.    You see the access path rebuilt messages, even though rebuilding
those access paths was faster than restoring them.

Had IBM been smart (ARGH, how many times have I used than expression), they
could have:

1.    Put a notation into the save information as to how many access paths
were suppressed.
2.    Not reported that those empty (fast) access path rebuilds occurred.

Al

Al Barsa, Jr.
Barsa Consulting Group, LLC

400>390

914-251-1234
914-251-9406 fax

http://www.barsaconsulting.com
http://www.taatool.com



                                                                           
             "Lopez, Andrew"                                               
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                                       SYSSAV & Access Paths               
             01/22/2004 07:34                                              
             AM                                                            
                                                                           
                                                                           
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We upgraded to an 810 this past weekend and ran into a problem with the use
of a full system save/restore (GO SAVE, option 21 with GO RESTORE, option
21).

We have 55 work libraries that are used to store order entry information as
it is being keyed.   The data is copied into production files once the
order
is confirmed.   Whenever we do a full system save, these files have no
data.


I am told by IBM Help Line that access paths for empty files are not saved
in a SYSSAV as of V5R2.   Indeed, after doing the restore onto the new box,
our order entry package would generate an error for each file in each of
the
work libraries.   While we could use EDTRBDAP, that is not acceptable in
our
view for disaster recovery purposes.   We are not interested in creating a
CL to open the files and force the rebuild.  We want backups that, once
restored, cause the system to run as it did when the objects were saved.

Saving the objects (via SAVLIB or SAVOBJ) with ACCPATH set to *YES works,
and if needed we will add this to our daily saves so that using GO RESTORE
option 21 and then overwriting with the latest daily will handle the
problem.   I can't say I'm thrilled by the prospect of backing up 55
libraries, with 37 files each, on a daily basis when they have no data in
them just to get the access paths.  My boss is not a fan of *IPL for the
RECOVER parameter.

So the question is, can I force the default behavior of a SYSSAV to save
all
access paths?  The IBM tech I spoke with couldn't point me to anything.
The OS/400 Backup and Recovery Guide V5R1 was no help and there doesn't
appear to be a V5R2 revision.
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