Re: WIP: store additional info in GIN index

On 2012-12-04 10:04:03 -0800, Josh Berkus wrote:
> On 12/4/12 9:34 AM, Robert Haas wrote:
> > On Sun, Nov 18, 2012 at 4:54 PM, Alexander Korotkov
> > <aekorotkov@gmail.com> wrote:
> >> Patch completely changes storage in posting lists and leaf pages of posting
> >> trees. It uses varbyte encoding for BlockNumber and OffsetNumber.
> >> BlockNumber are stored incremental in page. Additionally one bit of
> >> OffsetNumber is reserved for additional information NULL flag. To be able to
> >> find position in leaf data page quickly patch introduces small index in the
> >> end of page.
> > 
> > This sounds like it means that this would break pg_upgrade, about
> > which I'm not too keen.  Ideally, we'd like to have a situation where
> > new indexes have additional capabilities, but old indexes are still
> > usable for things that they could do before.  I am not sure whether
> > that's a realistic goal.
> 
> Is there a reason not to create this as a new type of index?  "GIN2" or
> whatever?

Aren't the obvious maintenance problems enough?

Greetings,

Andres Freund

-- 
 Andres Freund	                   http://www.2ndQuadrant.com/
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