On 26.2.2015 23:42, Kevin Grittner wrote:
> Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote:
>
>> Over the time I've heard various use cases for this patch, but in
>> most cases it was quite speculative. If you have an idea where
>> this might be useful, can you explain it here, or maybe point me to
>> a place where it's described?
>
>
> One use case is to be able to suppress default display of columns
> that are used for internal purposes. For example, incremental
> maintenance of materialized views will require storing a "count(t)"
> column, and sometimes state information for aggregate columns, in
> addition to what the users explicitly request. At the developers'
> meeting there was discussion of whether and how to avoid displaying
> these by default, and it was felt that when we have this logical
> column ordering it would be good to have a way tosuppress default
> display. Perhaps this could be as simple as a special value for
> logical position.
I don't see how hiding columns is related to this patch at all. That's
completely unrelated thing, and it certainly is not part of this patch.
--
Tomas Vondra http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
