Hi!
I had updated old patch with kNN operators for cube data structures. Copying description from old message:
Following distance operators introduced:
<#> taxicab distance
<-> euclidean distance
<=> chebyshev distance
For example:
SELECT * FROM objects ORDER BY objects.coord <-> '(137,42,314)'::cube LIMIT 10;
Also there is operator "->" for selecting ordered rows directly from index.
This request selects rows ordered ascending by 3rd coordinate:
SELECT * FROM objects ORDER BY objects.coord->3 LIMIT 10;
For descendent ordering suggested syntax with minus before coordinate.
This request selects rows ordered descending by 4th coordinate:
SELECT * FROM objects ORDER BY objects.coord->-4 LIMIT 10;
Stas Kelvich.
