The worlds smallest Slony cluster?

We recently updated on of our Slony clusters. I think it at least used to qualify as one of the worlds smallest ones:

  • Two nodes (obvious minimum)
  • one database (that's a given)
  • with one table
  • with one column
  • with one row

Now, we recently doubled the size of this cluster. It now has a whopping two columns in the table. The second column being updated by a trigger, so it's still only one column updated by the end user (well, application). But it's two columns to be replicated!

So what does this prove? Really, not much, but at least: Slony certainly scales "downward" just fine. It feels like a bit overhead to set it up for something like this, but it works just fine. Even in a small database, triggers can be very useful - regardless of what the documentation of a certain other database used to say before... And even in a trivial case like this, statement based replication simply does not work reliably*. You need something that's data based - something that the same other database is actually recognizing now and will be including the next version...


Conferences

I speak at and organize conferences around Open Source in general and PostgreSQL in particular.

Upcoming

PGConf.EU 2017
Oct 24-27, 2017
Warsaw, Poland
2Q PGconf
Nov 6-7, 2017
New York, USA
PGConf.Asia
Dec 4-6, 2017
Tokyo, Japan
FOSDEM PGDay 2018
Feb 2-4, 2018
Brussels, Belgium

Past

Inagural Oslo PUG meetup
Sep 12, 2017
Oslo, Norway
Postgres Open 2017
Sep 6-8, 2017
San Francisco, USA
PGDay.RU
Jul 5-7, 2017
St Petersburg, Russia
PGDay.UK
Jul 4, 2017
London, UK
Amsterdam PUG
Jun 29, 2017
Amsterdam, Netherlands
More past conferences