Re: BRIN range operator class

Heikki Linnakangas wrote:
> On 05/12/2015 10:49 PM, Alvaro Herrera wrote:
> >If in the future, for instance, we come up with a way to store the ipv4
> >plus ipv6 info, we will want to change the page format.  If we add a
> >page version to the metapage, we can detect the change at pg_upgrade
> >time and force a reindex of the index.
> 
> A version number in the metapage is a certainly a good idea. But we already
> have that, don't we? :
> 
> >/* Metapage definitions */
> >typedef struct BrinMetaPageData
> >{
> >    uint32        brinMagic;
> >    uint32        brinVersion;
> >    BlockNumber pagesPerRange;
> >    BlockNumber lastRevmapPage;
> >} BrinMetaPageData;
> >
> >#define BRIN_CURRENT_VERSION        1
> >#define BRIN_META_MAGIC            0xA8109CFA
> 
> Did you have something else in mind?

Yeah, I was thinking we could have a separate version number for the
opclass code as well.  An external extension could change that, for
instance.  Also, we could change the 'inclusion' version and leave
minmax alone.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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