Re: Design for In-Core Logical Replication

On 20/07/16 19:07, Simon Riggs wrote:
> On 20 July 2016 at 16:39, Joshua D. Drake <jd@commandprompt.com
> <mailto:jd@commandprompt.com>> wrote:
>             <para>
>               Logical Replication uses a Publish and Subscribe model
>         with one or
>               more Subscribers subscribing to one or more Publications on a
>               Provider node. Subscribers pull data from the Publications
>         they
>               subscribe to and may subsequently re-publish data to allow
>               cascading replication or more complex configurations.
>
>
>     Is that somehow different than Origin/Subscriber or Master/Slave? If
>     not, why are we using yet more terms?
>
>
> Thanks for asking, an important question that we have a chance to get
> right before we go too far down the road of implementation.
>
> I'll explain my thinking, so we can discuss the terms I've recommended,
> which can be summarized as:
> A Provider node has one or more Databases, each of which can publish its
> data in zero, one or more PUBLICATIONs. A Subscribing node can receive
> data in the form of zero, one or more SUBSCRIBERs, where each SUBSCRIBER
> may bring together data from one or more PUBLICATIONs
>
> Here's why...
>

Just to add to what Simon wrote. There is one more reason for not using 
term origin for this - origin of data does not necessarily have to be on 
the provider database once there is a cascading so it does not really 
map all that well.

--   Petr Jelinek                  http://www.2ndQuadrant.com/  PostgreSQL Development, 24x7 Support, Training &
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