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Re: odd behavior on client installation

From: Shakespeare <>
Date: Fri, 5 Oct 2007 14:52:23 +0200
Message-ID: <47063393$0$242$>

"EdStevens" <> schreef in bericht

> On Oct 5, 3:57 am, "Shakespeare" <> wrote:

>> "EdStevens" <> schreef in
>> > On Oct 3, 1:58 pm, EdStevens <> wrote:
>> >> Platform: Oracle 10.2 client on XP-Pro
>> > <snip>
>> > Solution found. Ripping out the \oracle directories and the \oracle
>> > key from HKLM wasn't enough. There was still an entry for tns_admin
>> > floating around in the system environment settings, and that was
>> > pointing to my original instant_client location. Apparently the OUI
>> > honors that and places the net config files there regardless of where
>> > ORACLE_HOME is located. And being an environment variable, it took
>> > precedence over the tns_admin in the registry when I opened a command
>> > window to run sqlplus.
>> > When I did another un-install, delete oracle directories and registry
>> > keys, *AND* clean up the system environment (My Computer, Properties)
>> > the install went exactly as I expected and have always seen it
>> > before.
>> Right. That's exactly what the TNS_ADMIN environment variable is for...
>> Shakespeare.
> Well, I knew what tns_admin is *for*!  But on Windoze systems I had
> never seen it anywhere but the registry (HKLM\software\oracle).  What
> was eluding me was the fact that it was set somewhere I wasn't
> expecting, leading to my purge of Oracle from the system being
> incomplete, leading to the next installation being influenced by the
> presence of environment settings being set from places I had never
> previously observed them being set.

There are more Oracle environment settings in different Oracle installations. I remember even one install (I think it was an upgrade of an old version of AS) removing some essential env. settings, without putting them back....
The TNS_ADMIN env. setting can be very useful; to override the tnsnames.ora temporarily, open a dos-box, put a tnsnames.ora in your temp dir and point to that dir with TNS_ADMIN. Because it overrules registry settings, and its temp. character (it is only valid for the specific DOS box and client programs started from it) you can easily circumvent tnsnames without having access to the registry (ideal for developers...). I agree though that an 'overall' tns_admin (system)environment setting can be confusing and misleading and should actually be set in the registry.

Shakespeare Received on Fri Oct 05 2007 - 07:52:23 CDT

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