UNIX vs XENIX & other misc

[reed]

Well, I'm about to take the big plunge and migrate from a real-time
mini to the DOS and UNIX/386 world. In short, I've got a new job developing
a LAN system. If anyone has some time to answer some basic questions for a
tyro, I'd appreciate it.

First off, what's the main difference or advantages between SCO UNIX and SCO
XENIX? Does it really matter which version I go with?

I'll be developing a network of 386 DOS machines tied to a UNIX/XENIX
server. The DOS language will be MS BASIC 7.0. I was thinking of using
LanManager and SQLManager most probably from SCO, again. Anything obviously
wrong with this scenario?

I'll need to support a database of approximately 300,000 transactions (each
transaction about 40 records, from 150 to 500 bytes per record). Will
LanManager and SQLManager handle this size odf database & this type of load?
I figure 2 600 Mb disk ought to be able to hold the databeses themselves.

Any suggestions or comments about whether this preliminary plan will work
would be appreciated (especially since my job is will be on the line!)