Reading a live database

I wonder how hard it would be to run a database server against a database 
that is already being run.  The idea is to be able to do read only queries 
against the database  from a different server on a shared NFS mounted 
database.  The second server would need to be able to start in a mode that 
ignored the lock and only allowed queries that read the database.  This would 
allow many intensive report queries against a busy transaction database.

Possible?  Possible with a little work?  A lot of work?

Another question, can a database server for one system (e.g. NetBSD on i386) 
run a database originally created on another (e.g. AIX on RS6000) or are 
there binary incompatibilities?

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.