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<DIV dir=ltr>Also noticed we have this same exercise repeated for touches, crosses, covers, within, disjoint. I guess pretty much any function where we would normally do an && in PostgreSQL before it hits these functions.</DIV></DIV>
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<DIV dir=ltr>The only place it doesn't seem redundant is in disjoint, but then again why don't we have disjoint using && in PostgreSQL.</DIV>
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<DIV dir=ltr>wouldn't we just restate ST_Disjoint to use indexes by doing the below</DIV>
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<DIV dir=ltr><BR> SELECT NOT ($1 && $2) OR _st_disjoint($1, $2) </DIV>
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<DIV dir=ltr>Thanks,</DIV>
<DIV dir=ltr>Regina</DIV>
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<DIV dir=ltr><FONT face=Tahoma size=2><B>From:</B> postgis-devel-bounces@postgis.refractions.net on behalf of Obe, Regina<BR><B>Sent:</B> Mon 9/8/2008 3:14 PM<BR><B>To:</B> postgis-devel@postgis.refractions.net<BR><B>Subject:</B> [postgis-devel] What's the point of this exercise in intersects?<BR></FONT><BR></DIV>
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<DIV><FONT face=Arial color=#000000 size=2>I was looking at the lwgeom_geos_c.c intersects function - starting at line 2039 and was thinking isnt' this</FONT></DIV>
<DIV><FONT face=Arial size=2>a bit redundant. By the time we get into this function we have already done a bounding box check. It probably isn't adding much overhead, but thought I would flag it as potentially redundant.</FONT></DIV>
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<DIV> /*<BR> * short-circuit 1: if geom2 bounding box does not overlap<BR> * geom1 bounding box we can prematurely return FALSE.<BR> * Do the test IFF BOUNDING BOX AVAILABLE.<BR> */<BR> if ( getbox2d_p(SERIALIZED_FORM(geom1), &box1) &&<BR> getbox2d_p(SERIALIZED_FORM(geom2), &box2) )<BR> {<BR> if ( box2.xmax < box1.xmin ) PG_RETURN_BOOL(FALSE);<BR> if ( box2.xmin > box1.xmax ) PG_RETURN_BOOL(FALSE);<BR> if ( box2.ymax < box1.ymin ) PG_RETURN_BOOL(FALSE);<BR> if ( box2.ymin > box2.ymax ) PG_RETURN_BOOL(FALSE);<BR> }</DIV>
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<DIV>thanks,</DIV>
<DIV>Regina</DIV>
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