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Re: logical changeset generation v3 - comparison to Postgres-R change set format

Markus Wanner <markus@bluegap.ch>

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From: Markus Wanner <markus@bluegap.ch>
To: Andres Freund <andres@2ndquadrant.com>
Cc: pgsql-hackers@postgresql.org
Date: 2012-11-17T09:22:40Z
Lists: pgsql-hackers 
On 11/16/2012 03:14 PM, Andres Freund wrote:
> Whats the data type of the "COID" in -R?

It's short for CommitOrderId, a 32bit global transaction identifier,
being wrapped-around, very much like TransactionIds are. (In that sense,
it's global, but unique only for a certain amount of time).

> In the patchset the output plugin has enough data to get the old xid and
> the new xid in the case of updates (not in the case of deletes, but
> thats a small bug and should be fixable with a single line of code), and
> it has enough information to extract the primary key without problems.

It's the xmin of the old tuple that Postgres-R needs to get the COID.

Regards

Markus Wanner

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Background worker processes

  2. Rearrange storage of data in xl_running_xacts.

  3. Basic binary heap implementation.

  4. Embedded list interface

  5. Refactor xlog.c to create src/backend/postmaster/startup.c