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Could somebody confirm the behavior of UNCATALOG & CATALOG command based on
the following situation:

There are two NODES on DB2 UDB v8.1, MYNODEA & MYNODEB. MYNODEA has two
databases proda & prodb & MYNODEB has an alias database dbload - catalog
from proda initially. Three end-users are currently connected to dbload.

NODE MYNODEA:
Databases:
PRODA
PRODB
NODE MYNODEB
DBLOAD (PRODA) (catalog from proda)


users connected to DBLOAD:

user1 - currently processing long running query
user2 - connected to DBLOAD doing nothing
user3 - connected to DBLOAD doing nothing

What will happen to these end-users after the following command is issued:
UNCATALOG DATABASE DBLOAD;
CATALOG DB PRODB AS DBLOAD AT NODE MYNODE;

Questions:
1) Is the query processing run by USER1 will stop?
2) What will happen to USER1, is it going to be disconnected?
3) What will happen to USER1 & USER2, are they automatically disconnected as
well & if they run queries after UNCATALOGing the DBLOAD, can they still run
the query & which database they are pointing to?


Your help would be highly appreciated.


maricel.

maricel <maricel@xtra.co.nz> wrote:

> Could somebody confirm the behavior of UNCATALOG & CATALOG command based
> on the following situation:
>
> There are two NODES on DB2 UDB v8.1, MYNODEA & MYNODEB. MYNODEA has two
> databases proda & prodb & MYNODEB has an alias database dbload - catalog
> from proda initially. Three end-users are currently connected to dbload.
>
> NODE MYNODEA:
> Databases:
> PRODA
> PRODB
> NODE MYNODEB
> DBLOAD (PRODA) (catalog from proda)
>
>
> users connected to DBLOAD:
>
> user1 - currently processing long running query
> user2 - connected to DBLOAD doing nothing
> user3 - connected to DBLOAD doing nothing
>
> What will happen to these end-users after the following command is issued:
> UNCATALOG DATABASE DBLOAD;
> CATALOG DB PRODB AS DBLOAD AT NODE MYNODE;

Nothing. They are still connected to PRODA.

> Questions:
> 1) Is the query processing run by USER1 will stop?

No.

> 2) What will happen to USER1, is it going to be disconnected?

No.

> 3) What will happen to USER1 & USER2, are they automatically disconnected
> as well & if they run queries after UNCATALOGing the DBLOAD, can they
> still run the query & which database they are pointing to?

They stay connected and run their queries against PRODA.

The db2agent processes that act on behalf of your users have the directory
information cached. The cache is not changed on the fly.

--
Knut Stolze
Information Integration
IBM Germany / University of Jena

Thanks for this info.
How are you going to re-direct those currently connected users to point to
the new database?
Is there a mechanism to update their directory cache to point to PRODB on
the fly?

Many Thanks,
maricel

"Knut Stolze" <stolze@de.ibm.com> wrote in message
news:c0fane$uf7$1@fsuj29.rz.uni-jena.de...
> maricel <maricel@xtra.co.nz> wrote:
>
> > Could somebody confirm the behavior of UNCATALOG & CATALOG command based
> > on the following situation:
> >
> > There are two NODES on DB2 UDB v8.1, MYNODEA & MYNODEB. MYNODEA has two
> > databases proda & prodb & MYNODEB has an alias database dbload - catalog
> > from proda initially. Three end-users are currently connected to dbload.
> >
> > NODE MYNODEA:
> > Databases:
> > PRODA
> > PRODB
> > NODE MYNODEB
> > DBLOAD (PRODA) (catalog from proda)
> >
> >
> > users connected to DBLOAD:
> >
> > user1 - currently processing long running query
> > user2 - connected to DBLOAD doing nothing
> > user3 - connected to DBLOAD doing nothing
> >
> > What will happen to these end-users after the following command is
issued:
> > UNCATALOG DATABASE DBLOAD;
> > CATALOG DB PRODB AS DBLOAD AT NODE MYNODE;
>
> Nothing. They are still connected to PRODA.
>
> > Questions:
> > 1) Is the query processing run by USER1 will stop?
>
> No.
>
> > 2) What will happen to USER1, is it going to be disconnected?
>
> No.
>
> > 3) What will happen to USER1 & USER2, are they automatically
disconnected
> > as well & if they run queries after UNCATALOGing the DBLOAD, can they
> > still run the query & which database they are pointing to?
>
> They stay connected and run their queries against PRODA.
>
> The db2agent processes that act on behalf of your users have the directory
> information cached. The cache is not changed on the fly.
>
> --
> Knut Stolze
> Information Integration
> IBM Germany / University of Jena

If you do not want to have to update any client files, then you will have to
work from MYNODEB. Make sure that on MYNODEB, the instance that owns DBLOAD
is active.
Beacuase DBLOAD is the alias of PRODA it means that MYNODEA is already
identified to MYNOEDB
UNCATALOG DATABASE DBLOAD
CATALOG DATABASE PRODB AS DBLOAD AT NODE MYNODEA

As these execute, whoever was connected to PRODA via DBLOAD will stay there
until they connect reset,
I believe that for the new connection requests, instead of reading the
cache, the instance will realize that the file has been changed and the new
connection requests should go to to PRODB via DBLOAD.

To ensure that it is the case, if you can afford it, stop/start the
instance. If not, and you're on V*, look at using the QUIESCE command at
either/or the instance or db level.
HTH, Pierre.
"maricel" <maricel@xtra.co.nz> a écrit dans le message de
news:qn0Xb.42978$9k7.887157@news.xtra.co.nz...
> Thanks for this info.
> How are you going to re-direct those currently connected users to point to
> the new database?
> Is there a mechanism to update their directory cache to point to PRODB on
> the fly?
>
> Many Thanks,
> maricel
>
> "Knut Stolze" <stolze@de.ibm.com> wrote in message
> news:c0fane$uf7$1@fsuj29.rz.uni-jena.de...
> > maricel <maricel@xtra.co.nz> wrote:
> >
> > > Could somebody confirm the behavior of UNCATALOG & CATALOG command
based
> > > on the following situation:
> > >
> > > There are two NODES on DB2 UDB v8.1, MYNODEA & MYNODEB. MYNODEA has
two
> > > databases proda & prodb & MYNODEB has an alias database dbload -
catalog
> > > from proda initially. Three end-users are currently connected to
dbload.
> > >
> > > NODE MYNODEA:
> > > Databases:
> > > PRODA
> > > PRODB
> > > NODE MYNODEB
> > > DBLOAD (PRODA) (catalog from proda)
> > >
> > >
> > > users connected to DBLOAD:
> > >
> > > user1 - currently processing long running query
> > > user2 - connected to DBLOAD doing nothing
> > > user3 - connected to DBLOAD doing nothing
> > >
> > > What will happen to these end-users after the following command is
> issued:
> > > UNCATALOG DATABASE DBLOAD;
> > > CATALOG DB PRODB AS DBLOAD AT NODE MYNODE;
> >
> > Nothing. They are still connected to PRODA.
> >
> > > Questions:
> > > 1) Is the query processing run by USER1 will stop?
> >
> > No.
> >
> > > 2) What will happen to USER1, is it going to be disconnected?
> >
> > No.
> >
> > > 3) What will happen to USER1 & USER2, are they automatically
> disconnected
> > > as well & if they run queries after UNCATALOGing the DBLOAD, can they
> > > still run the query & which database they are pointing to?
> >
> > They stay connected and run their queries against PRODA.
> >
> > The db2agent processes that act on behalf of your users have the
directory
> > information cached. The cache is not changed on the fly.
> >
> > --
> > Knut Stolze
> > Information Integration
> > IBM Germany / University of Jena
>
>