Re: Changeset Extraction v7.3

On Tue, Jan 28, 2014 at 11:53 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> I've rebased it here and am hacking on it still.

Andres and I are going back and forth between our respective git repos
hacking on this, and I think we're getting there, but I have a
terminological question which I'd like to submit to a wider audience:

The point of Andres's patch set is to introduce a new technology
called logical decoding; that is, the ability to get a replication
stream that is based on changes to tuples rather than changes to
blocks. It could also be called logical replication. In these
patches, our existing replication is referred to as "physical"
replication, which sounds kind of funny to me. Anyone have another
suggestion?

There are a lot of ways to slice the space of possible replication
solutions. We currently talk about "streaming replication" (as
opposed to "archiving") and "synchronous replication" (as opposed to
asynchronous), but this is a new distinction. At least in theory,
whether replication is "physical" or logical is independent of whether
it's based on streaming or archiving and also of whether it's
synchronous or asynchronous. So we can't for example talk about
"logical replication" in opposition to "streaming replication"; that's
comparing apples and oranges. We need a pair of new terms, and I
can't immediately think of anything better than physical/logical, but
it still sounds somewhat awkward to me so ... anyone else have an
idea?

Thanks,

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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