Hello Bruce,

Bruce Momjian wrote:
Here is a new replication documentation section I want to add for 8.2:

        ftp://momjian.us/pub/postgresql/mypatches/replication

Comments welcomed.

Thank you, that sounds good. It's targeted to production use and currently available solutions, which makes sense in the official manual.

You are explaining the sync vs. async categorization, but I sort of asked myself where the explanation of single vs multi-master has gone. I then realized, that you are talking about read-only and a "read/write mix of servers". Then again, you are mentioning 'Multi-Master Replication' as one type of replication solutions. I think we should be consistent in our naming. As Single- and Multi-Master are the more common terms among database replication experts, I'd recommend to use them and explain what they mean instead of introducing new names.

Along with that, I'd argue that this Single- or Multi-Master is a categorization as Sync vs Async. In that sense, the last chapter should probably be named 'Distributed-Shared-Memory Replication' or something like that instead of 'Multi-Master Replication', because as we know, there are several ways of doing Multi-Master Replication (Slony-II / Postgres-R, Distributed Shared Memory, 2PC in application code or the above mentioned 'Query Broadcast Replication', which would fall into a Multi-Master Replication model as well)

Also in the last chapter, instead of just saying that "PostgreSQL does not offer this type of replication", we could probably say that different projects are trying to come up with better replication solutions. And there are several proprietary products based on PostgreSQL which do solve some kinds of Multi-Master Replication. Not that I want to advertise for any of them, but it just sounds better than the current "no, we don't offer that".

As this documentation mainly covers production-quality solutions (which is absolutely perfect), can we document the status of current projects somewhere, probably in a wiki? Or at least mention them somewhere and point to their websites? It would help to get rid of all those rumors and uncertainties. Or are those intentional?

Just my two cents.

Regards

Markus

---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
      choose an index scan if your joining column's datatypes do not
      match

Reply via email to