Database Design for use with XSQL-connected Clients

Hi all,
this might seem a little off-topic at first, but I suppose we are not the only ones reading this group designing an architechture using XSQL servlet as the only connection to the database, with clients connecting over the internet.
So far our approach works well, but of course any database round trip is much more expensive in this environment than with clients that hold an open connection to the database.
That led us to the idea of generating primary keys on the client instead of the database (e.g. with CoCreateGuid on Win32). Do those GUIDs have to be stored in the Oracle database in a RAW column or does a NUMBER field do the job?
I found a hint in the Oracle 8i Replication manual to use SYS_GUID values in a RAW(32) column as a primary key to avoid conflicts between sequences on multiple machines. But I didn't find any statement concerning the performance issues of this.
Our database will not store huge amounts of data (most tables < 100.000 rows, just a handful more than a million in huge environments, which will be able to afford huge machines...), so this should not be
a problem, I guess.
Does anyone of you have experience with this?
And another question: Can I safely assume that keys generated with SYS_GUID on the Oracle server will not likely be the same as those that are generated using CoCreateGuid on the Win32 client?
Thanks for your input.
Olaf Lewitz
ohltec SOFTWERFT, Hamburg

Don't GUID's have hyphens in them? If so, you'd have to use a VARCHAR2(xx) of appropriate length. If not, then you can likely use HEX_TO_RAW() and RAW_TO_HEX() to store then in a RAW as you've noted.
Note that the XSQL Servlet's default connection manager does to connection pooling, so the roundtrip to the database may not be as expensive as you're thinking. :-)

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Database Design for use with XSQL-connected Clients

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