RDBMS Server Performance Expectations

I'm working on a MIS project which has some scalability issues with its RDBMS, so I'm looking for comments from users of other RDBMS platforms. I don't have any experience on "big" RDBMS such as Informix or Oracle so as much as anything I'm looking for guidance on what behaviour we should reasonably expect. The project is using the Raima "Velocis SQL Server" on Netware 3.12 & 4.1, and Windows NT TCP/IP platforms, with record sizes up to around 1kB. Some tables contain tens of thousands of records and on large sites will may contain a few millions. Some trends have emerged that bother us:

1. The server RAM required during a SQL transaction appears to be one to two times the total size of modified records, i.e. updating 1,000 1kB records increases the SQL server's RAM allocation by about 2MB. This can lead to server crashing, e.g. "update TBL set NUM = 0;" can fail on a server with 96MB of RAM with a table size of several tens of thousands of records:
   1. do such broad updates work in general? If not, then how do people do such things as adding 10% to every stock item price?
   2. do RDBMS generally eat RAM this fast in transactions?
2. The size of records on the disk appears to be around the sum of field sizes PLUS the size of every instance of a field in each key. The data seems quite loosely packed; the database files typically PKZIPs to less than 10% of the original size. For our larger clients (keeping several million records) this will produce databases several gigabytes in size. Are other SQL databases more compact?
3. By PC standards the server hardware employed is moderate, e.g. 120MHz Pentium with 64MB RAM (Top-end "off the shelf" PC hardware (e.g. quad Pentium-Pro 200MHz) might (perhaps) run 10 times faster). This has performance around 1-10 insertions per second, 2-5 deletions per second, 10-50 find/reads per second.
   1. On a similar level of hardware, how does this performance rate?
   2. What sort of hardware is used for other RDBMS with a similar size of databases (10,000 - 1,000,000 records?)

Many thanks for any advice you can give (and apologies for chucking into this and a couple of related newsgroups). I'd also be particularly interested to hear from any other large-scale Velocis users.

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• Dr. John Hamer Email: J.Hamer_at_cs.auckland.ac.nz
• Department of Computer Science http://www.cs.auckland.ac.nz
• University of Auckland Phone: +64 9 3737 599 x8758
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