Re: Questions about support function and abbreviate

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От Darafei "Komяpa" Praliaskouski
Тема Re: Questions about support function and abbreviate
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Msg-id CAC8Q8tJzY1DcyfE4cS8hrnJKzgP4SLbbxyNMNFyA+4BVYgpqeA@mail.gmail.com
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Ответ на Questions about support function and abbreviate  (Han Wang <hanwgeek@gmail.com>)
Ответы Re: Questions about support function and abbreviate  (Han Wang <hanwgeek@gmail.com>)
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Hello,

the abbrev_converter is applied whenever it is defined. The values are sorted using the abbreviated comparator first using the shortened version, and if there is a tie the system asks the real full comparator to resolve it. 

This article seems to be rather comprehensive: https://brandur.org/sortsupport

On Sat, Jun 12, 2021 at 9:51 AM Han Wang <hanwgeek@gmail.com> wrote:
Hi all,

I am trying to implement a sort support function for geometry data types in PostGIS with the new feature `SortSupport`. However, I have a question about this.

I think it is hardly to apply a sort support function to a complex data type without the `abbrev_converter` to simply the data structure into a single `Datum`. However, I do not know how the system determines when to apply the converter.

I appreciate any answers or suggestions. I am looking forward to hearing from you.

Best regards,
Han


--
Darafei "Komяpa" Praliaskouski
OSM BY Team - http://openstreetmap.by/

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