Re: Cube extension kNN support

<div dir="ltr">Do you have any benchmarks ?<br /></div><div class="gmail_extra"><br /><br /><div class="gmail_quote">On
Mon,Sep 23, 2013 at 3:38 AM, Stas Kelvich <span dir="ltr"><<a href="mailto:stas.kelvich@gmail.com"
target="_blank">stas.kelvich@gmail.com</a>></span>wrote:<br /><blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px#ccc solid;padding-left:1ex">Hello, hackers.<br /><br /> Here is the patch that introduces kNN
searchfor cubes with euclidean, taxicab and chebyshev distances.<br /><br /> Following distance operators
introduced:<br/><br /> <#> taxicab distance<br /> <->  euclidean distance<br /> <=> chebyshev
distance<br/><br /> For example:<br /> SELECT * FROM objects ORDER BY objects.coord <-> '(137,42,314)'::cube
LIMIT10;<br /><br /> Also there is operator "->" for selecting ordered rows directly from index.<br /> This request
selectsrows ordered ascending by 3rd coordinate:<br /><br /> SELECT * FROM objects ORDER BY objects.coord->3 LIMIT
10;<br/><br /> For descendent ordering suggested syntax with minus before coordinate.<br /> This request selects rows
ordereddescending by 4th coordinate:<br /><br /> SELECT * FROM objects ORDER BY objects.coord->-4 LIMIT 10;<br /><br
/>Stas Kelvich.<br /><br /><br /><br /><br /> --<br /> Sent via pgsql-hackers mailing list (<a
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