Re: create opclass documentation outdated - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: create opclass documentation outdated
Date
Msg-id 20160302182107.GA433470@alvherre.pgsql
Whole thread Raw
In response to Re: create opclass documentation outdated  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: create opclass documentation outdated
List pgsql-hackers
Tom Lane wrote:

> In create_opclass.sgml, not only do we have the list of AMs supporting
> STORAGE, but there is also a paragraph describing which AMs do what
> for input datatypes of FUNCTION members (around line 175).

I placed BRIN together with gist/gin/spgist here, namely that the optype
defaults to the opclass' datatype.

> xindex.sgml has that one list you mentioned, but there's not much
> point in fixing that when BRIN indexes fail to be described either in
> 35.14.2 or 35.14.3, where they certainly should be.  And there are
> other places throughout that chapter that say that such-and-such AMs
> support each feature as it's discussed.

In 35.14.2 I added the table of strategies in the "minmax" opclasses;
the list for the "inclusion" opclasses would be much longer.  Since GIN
doesn't document anything other than its array support, I'm not really
sure that we want/need to document the "inclusion" opclasses also.

In 35.14.3 I added the table of four basic support procs.  I think
that's all that's strictly necessary.  For inclusion we have a bunch of
additional support procs.

I also added a paragraph to 35.14.5, indicating that "minmax" is pretty
much the same as btree.  "Inclusion" opclasses are supposed to support
cross-datatype operators too (supposedly we could support
above/below/containment etc for points relative to boxes, for example,
if we got around to make a decision regarding floating point comparisons
in geometry operators), but we don't have any, so I hesitate to say
anything about this.

Patch attached.

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

Attachment

pgsql-hackers by date:

Previous
From: Peter Geoghegan
Date:
Subject: Re: Commitfest Bug (was: Re: Reusing abbreviated keys during second pass of ordered [set] aggregates)
Next
From: Tom Lane
Date:
Subject: Re: Convert pltcl from strings to objects