Re: Oracle Snapshots

>>In article <46ipd3$7qi_at_info1.sdrc.com> "Dana M. Riley" <dmriley> writes:  

>>>I have an application where, for performance reasons, I would like to
>>>replicate a read-only copy of a database overseas. The initial database
>>>is approximately 1GByte with approximately 250KB/Day of additions and/or
>>>modifications. I am considering using Snapshots for this application.
>>>I have two questions. How well do snapshots work with Oracle 7.1.6? (I
>>>had been told that snapshots did not work well in 7.0.?)

Snapshot refresh groups (a group of tables refreshed in a single transaction) has been around at least since 7.1.3.

I have had a number of problems with snapshots; the two most serious were:

1. Snapshot log does not purge after fast refresh, with between 10,000 and 20,000 row changed applied, of large snapshots. This problem necessitated abandoning snapshots altogether for these tables and writing my own workaround.
2. Bogus rowids written to snapshot logs. The rowids were of rows in the log itself, not the logged table.

   ---

Paul Baumgartel, Principal Consultant              paulb_at_pcnet.com 
Adept Computer Associates, Inc.                                    
********************************************************************