Craig Ringer wrote:
On Mon, 2009-06-22 at 21:29 -0400, Gerry Reno wrote:
I don't know how it could guarantee that. That's really why row-based
is better.
Yep, especially in the face of things like user PL functions, C
functions, etc.
This page:
http://dev.mysql.com/doc/refman/5.0/en/replication-features-functions.html
is downright alarming, and (implicitly) says quite enough about how
statement-based replication is a really, REALLY bad idea.
Rather than replicating sets of changed rows, though, I suspect that
block-level replication using the WAL is probably more efficient.
Certainly it'll be easier on the slave in terms of the work required to
keep up with the master.
I guess block-level replication isn't much good for multi-master,
though, since you'd be spending half your time finding out what the
other masters were doing and what their state was, or telling them about
yours. (I guess that's the case anyway to some extent, though, any time
you have concurrent statements on different masters using the same data
and one or more of them is altering it).
Sequences I deal with by setting up an offset and increment for each
replica so that there are no conflicts.
Ah, so you don't actually care if the replicas are identical - you
expect things like different primary keys on master and replicas(s) ?
How do your applications cope if they switch from one replica to another
and suddenly primary key identifiers are different?
Here is a link that describes the technique:
http://www.onlamp.com/pub/a/onlamp/2006/04/20/advanced-mysql-replication.html?page=1 <snip>
Regards,
Gerry
