On Sun, 7 Sep 2008, M2Y wrote:

Why does a replication solution need log shipping and why cant we just
ship the transaction statements to a standby node?

Here's one of the classic examples of why that doesn't work:

create table x (d decimal);
insert into x values (random());

If you execute those same statements on two different nodes, they will end up with different values for the random number and therefore the nodes won't match anymore. A similar issue shows up if you use functions that check the current system time, that will be slightly different between the two: even if the clocks are perfectly synced, by the time the standy received the transaction it will be later than the original.

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* Greg Smith [EMAIL PROTECTED] http://www.gregsmith.com Baltimore, MD

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