Re: pgsql: Only WAL-log the modified portion in an UPDATE, if possible.

On 12 March 2014 21:30, Heikki Linnakangas <heikki.linnakangas@iki.fi> wrote:
> Only WAL-log the modified portion in an UPDATE, if possible.
>
> When a row is updated, and the new tuple version is put on the same page as
> the old one, only WAL-log the part of the new tuple that's not identical to
> the old. This saves significantly on the amount of WAL that needs to be
> written, in the common case that most fields are not modified.
>
> Amit Kapila, with a lot of back and forth with me, Robert Haas, and others.

Nice tight, useful patch. Very neat, well done all.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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