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<TITLE>RE: [postgis-users] Why choose PostGIS?</TITLE>
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<P><FONT SIZE=2>Alan,<BR>
<BR>
MySQL's spatial functionality is very limited IMHO -- they only have a bounding box intersection, similar to the && operator, and nothing like a "within" or distance function. So if you have, say, a lot of rectangular tiles and a query shape that is a large semi-circle, both MySQL and postGIS return the same bounding box search results. But if you want only tiles that are completely within the query shape MySQL can't give you that. I posted a query a few weeks ago about a related issue; I think I included an image of query shape. The BB query gets back a thousand or so candidates; the actual ones within are a few dozen. Trying to handcode an application to deal with this would be prohibitively ugly. And of courser PostgreSQL itself has some features that MySQL either does not have at all or are very new and untried.<BR>
<BR>
This is based on an informal evaluation we did a couple of weeks ago in house; sorry I can;t provide any links. MySQL 5.x is fairly new and I don't know of any benchmarks comparing it.<BR>
<BR>
Sorry for top posting -- challenged mail reader.<BR>
<BR>
<BR>
Greg Williamson<BR>
Senior DBA<BR>
GlobeXplorer LLC, a DigitalGlobe company<BR>
<BR>
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-----Original Message-----<BR>
From: postgis-users-bounces@postgis.refractions.net on behalf of Alan Cunnane<BR>
Sent: Tue 8/7/2007 5:42 PM<BR>
To: PostGIS Users Discussion<BR>
Subject: [postgis-users] Why choose PostGIS?<BR>
<BR>
Hey guys<BR>
<BR>
I have been using PostGIS for my dissertation now for 6 months and have found it extremely useful, fast and understandable and along with the support you get from this mailing group I have never regretted this decision. However as i am completing my write up I cant seem to find any solid literature or independant reliable benchmarking tests that would show why a user would choos PostGIS for spatial queries over say MySQL. I have read in some places that MySQL is not as OGC compliant as PostGIS however I need an official source to prove this.<BR>
<BR>
Can anyone send me any links to such proof or recommend any literature on this matter? Even one reference would do.<BR>
<BR>
Thanks<BR>
<BR>
Alan<BR>
<BR>
<BR>
<BR>
<BR>
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