Re: handling of heap rewrites in logical decoding

On 2/25/18 07:27, Craig Ringer wrote:
> I'm pretty sure we _will_ want the ability to decode and stream rewrite
> contents for non-IMMUTABLE table rewrites.
> 
> Filtering out by default is OK by me, but I think making it impossible
> to decode is a mistake. So I'm all for the oid option and had written a
> suggestion for it before I saw you already mentioned it  in the next
> part of your mail.
> 
> The main issue with filtering out rewrites by default is that I don't
> see how, if we default to ignore/filter-out, plugins would indicate
> "actually I want to choose about this one" or "I understand table
> rewrites". I'd prefer not to add another change callback.

Second version, which uses an OID.  I added another field to the output
plugin options (next to the output_type), to indicate whether the plugin
wants to receive these changes.  I added some test cases to
test_decoding to show how it works either way.  It's a bit messy to pass
this setting through to the ReorderBuffer; maybe there is a better idea.
 But the result seems pretty useful.

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services