Re: DB2/400 <--> Oracle Questions

"Charles Wilt" <cwilt_at_meaa.mea.com> schreef in bericht news:MPG.1c339b65c61ffb56989722_at_news.easynews.com...
> Ok,
>
> It appears that Oracle provides 3 (ok 4) products related to
> DB2/400 <--> Oracle access:
>
> 1) Oracle Transparent Gateway for DB2/400
> --runs on iSeries
> --Handles Oracle --> DB2/400 access
> --TCP/IP
> 2) Oracle Transparent Gateway for DRDA
> --runs on a host system (Windows, UNIX, Linux, ect)
> --handles Oracle --> DB2/400 access (or any other DRDA server)
> --uses SNA or TCP/IP
> 3) Oracle Access Manager for AS/400
> --runs on iSeries
> --Handles DB2/400 --> Oracle access
> --uses TCP/IP
>
> 4) Oracle Generic Connectivity
> --runs on Oracle System
> --Handles Oracle --> DB2/400 access
> --uses ODBC or OLEDB driver to access DB2/400
>
> IBM Provides one product:
>
> 1) DB2 Information Integrator (formally DataJoiner)
> --runs on a (non-iSeries) host system
> --Handles DB2/400 --> Oracle access
> --uses TCP/IP
>
>
> Now it appears Oracle packages options 1-3 together at a cost of
> $35,000. Option 4 is built into the Oracle DB software already.
>
> IBM's product is $25,000 to $50,000 depending on rather I need the
> Advanced edition or could use the Standard edition.
>
>
> Given that the Oracle solution provides bidirectional capabilities, it
> would appear to be the solution of choice.
>
> However, does anyone have any experience/comments about the above
> products?
>
> In particular:
> --Is there any reason to choose the Oracle DRDA TG over the DB2/400 TG
> given that we have only the iSeries to connect to and plenty of CPU to
> spare on our iSeries?
>
> --What we are looking for is the ability to access remote tables as
> local tables in order to eliminate real-time replication requirements.
> Is this really possible? Can you do this with acceptable performance?
> Could we replace a PF (Table) on the iSeries with a link to a table in
> Oracle (without rewriting a bunch of old RPG programs)? Any
difference
> in performance between Oracle link to DB2/400 and DB2/400 link to
> Oracle?
>
> --Does the Oracle TG products offer $35,000 with of improvement over
the
> capabilities of the Generic Connectivity option? I realize that the
TG
> option include bidirectional access whereas the Generic Connectity
> option doesn't.
>
> Thanks in advance,
> Charles Wilt

Hi Charles,

My experience with the Oracle Transparent Gateway (OTG) dates from 1999, so I have to dig up stuff from memory. Some findings may be outdated as well.

OTG works well, but is not a friendly product. What I mean by that is that the documentation is ambiguous, so when I went and updated the original installation I cleared everything out, since there were a couple of libraries left from the default installation that were never used, as well as service programs and other objects that belonged to an even older version but never removed, as nobody dared to kill stuff that seemed superfluous.

So, once you get the hang of it, it's a small and clean installation (if you care to sort things out and clean up) with very little overhead on the CPU, so I wouldn't worry about that. What you have to bear in mind is that Oracle cannot connect to any file member other than *first, so if you use multi-member files you need to set up a single logical for every physical member and access your file members through the logicals. The Oracle service library is a great place for keeping those members, since they're really only there for Oracle's use.

Oracle will read and write to the DB2/400 files as if they were Oracle tables (think of it like DDM RDB access). Performance is OK, but then again, my client only used it for interfacing and not for numerous read/writes on a continuous basis. So I cannot tell you whether performance is OK if you'd use the DB2/400 file as an application table that's being accessed and updated by lots of processes.

Whether it's worth the money would depend on what you need. I'd personally not go for a host-in-the-middle DRDA solution, if only for the fact you'd introduce another source for trouble. I'm not familiar with the 'native' solution, but I'm not that impressed with ODBC, so I guess the OTG solution would perform better. Having said that, as you state, if you need bi-directional access you wouldn't have much choice anyway...

If in doubt, I'd get a test-license in order to do some comparing and benchmark testing. I don't think there is (was?) a license key tying it to a specific system , or there may be some grace period that should allow you to try before you buy.

HTH Regards, best wishes and all that,

René Received on Thu Dec 23 2004 - 11:08:42 CST