How smart are Snapshots ?

Hi,

I was just wondering how smart Oracle behaves in the create snapshot statement.

The situation is that we have a table that needs to be distributed on a regular basis to several other locations. The table will have potentially up to a million records. During busy hours of the day several selects per second might be necessary from this table, and that is the reason we don't want to do that over the network, but would rather have every location have it's own snapshot to work with and update the snapshot on a regular basis. (The original table will only be updated on demand, and after such an update an update of all snapshots could be triggered).

When I say "update snapshot", will Oracle basically copy the whole table again, or will it be smart enough to know where the table has been changed since the last update snapshot and only copy whatever has been changed ?

Heber Ferraz-Leite

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H.Ferraz-Leite_at_fsc.at

Ferraz-Leite Software Engineering & Consulting KEG
http://www.fsc.at