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<DIV dir=ltr align=left><SPAN class=683041120-30092014><FONT size=4>I would say
probably not worth pursuing. KNN gist for geography is much more useful of
a pursuit I think :)</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=683041120-30092014><FONT
size=4>Thanks,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=683041120-30092014><FONT
size=4>Regina</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=683041120-30092014><FONT
size=4></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=683041120-30092014><FONT
size=4></FONT></SPAN> </DIV><BR>
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<FONT size=2 face=Tahoma><B>From:</B> postgis-devel-bounces@lists.osgeo.org
[mailto:postgis-devel-bounces@lists.osgeo.org] <B>On Behalf Of </B>Paul
Ramsey<BR><B>Sent:</B> Tuesday, September 30, 2014 2:45 PM<BR><B>To:</B> PostGIS
Development Discussion<BR><B>Subject:</B> [postgis-devel] SP-GIST: what to
do<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px">Hey
all,</DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px"><BR></DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px">So,
I’ve now got a working sp-gist implementation</DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px"><BR></DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px">https://github.com/pramsey/postgis/tree/spgist/</DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px"><BR></DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px">(Build
and install, and after enabling postgis also run the commands
in gserialized_spgist_2d.sql to add the spgist functions and opclass)</DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px"><BR></DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px">This
is a copy of the quadtree implementation Teodor put into PgSQL, but bound to our
‘geometry’ type. It is also restricted to points only (though, non-optimally, I
cannot throw a “not a point” error until I get into the picksplit routine, so
it’s possible to build a small index on non-point features… just how to handle
that corner case is something I have yet to figure out).</DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px"><BR></DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px">The
question is whether to continue to pursue this work for 2.2. Given the lack of a
“compress” hook for spgist, support for anything other than points seems
problematic. Similarly, the corner case above could have potentially deleterious
effects. Also, since we have a cast from geometry::point (for geometries that
are points), it’s possible for people to build functional spgist indexes
*already*, if they like (though they won’t have as good stats/planning as
geometry, since the spatial stats code in postgresql proper is lacking)</DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px"><BR></DIV>
<DIV id=bloop_customfont
style="FONT-SIZE: 13px; FONT-FAMILY: Helvetica,Arial; COLOR: ; MARGIN: 0px">I
feel like the lack of support for all geometry variants, and the inability to
cleanly restrict the index to just a point variant in combination make spending
more effort on a direct geometry binding probably not worth it, though I’m
willing to entertain counter arguments.</DIV>
<DIV><BR></DIV>P<BR>
<DIV id=bloop_sign_1412102364444082944 class=bloop_sign>
<DIV><BR></DIV>-- <BR><B>Paul Ramsey</B>
<DIV>
<DIV>pramsey@boundlessgeo.com </DIV>
<DIV>250-885-0632 </DIV>
<DIV>@boundlessgeo </DIV>
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