← Back to team overview

maria-developers team mailing list archive

Re: Row-based replication of old DECIMAL to new DECIMAL

 

Hi, Jeremy!

On Feb 12, Jeremy Cole wrote:
> Howdy,
> 
> > d. Make the master running with --binlog-format=row refuse to do any
> > >  INSERT/UPDATE/ALTER or any other queries that can modify a table
> > >  with the old DECIMAL.
> 
> Note that currently such DECIMAL columns work just fine with RBR, so
> long as the master and slave have the same internal types. So
> completely disallowing DECIMAL with RBR seems like a breaking and
> unnecessary change to something which apparently works fine for the
> user already.

Right. That's why I didn't particularly like that idea. Because quite
often old DECIMAL works just fine with RBR.

On the other hand, the master cannot know whether tables on the slave
are compatible with old DECIMAL or not. And by the time the replicated
row events reach the slave it's too late to stop them - replication is
already broken.

At the moment I, frankly, cannot think of any satisfactory solution for
this.

> I should hope this strategy is not taken here, and certainly should
> not be taken as precedent for how to do things in the future.

Regards,
Sergei


Follow ups

References