<div><div><div class="gmail_quote">On Wed, Jul 6, 2011 at 5:51 PM, Even Rouault <span dir="ltr"><<a href="mailto:even.rouault@mines-paris.org">even.rouault@mines-paris.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="im">It is just that CreateLayer() will declare the geometry as being Polygon, but</div>
insert MultiPolygon sometimes. That's one of the caveats with the shapefile<br>
format/driver that will report a layer as being of type wkbPolygon but can<br>
return geometries that might actually be POLYGON or MULTIPOLYGON.<br>
<br>
Clearly, CreateLayer() is a simplistic implementation that doesn't have all<br>
the subtelties and options of ogr2ogr... With ogr2ogr, you would typically<br>
workaround this by using the -nlt MULTIPOLYGON option that would convert<br>
polygons to multipolygons before passing them to the PG driver.<br></blockquote><div><br></div></div><div class="gmail_quote">Well isn't that embarrassing ... this caveat is the third paragraph of the ESRI shapefile driver page. Thanks for your time, Even.</div>
<div class="gmail_quote"><br></div><div class="gmail_quote">I'm looking at the shapefile driver now; out of curiosity, is there a benefit to having SHPT_POLYGON shapefiles return wkbPolygon instead of wkbMultiPolygon as their GeomType or SHPT_ARC shapefiles return wkbLineString instead of wkbMultiLineString? Would having the driver return the "Multi" geometry flavor instead cause a catastrophic failure somewhere? Or is it a performance issue?</div>
<div class="gmail_quote"><br></div><div class="gmail_quote">Is there a discussion thread I could read to catch up on this?</div><div class="gmail_quote"><br></div></div></div><div><div><div>-----<br></div></div><div>Luke Peterson</div>
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