Hi everyone,<br><a href="http://postgis.refractions.net/docs/ST_DWithin.html">http://postgis.refractions.net/docs/ST_DWithin.html</a><br>I see the ST_DWithin function that we can we can determine the geometries are within a specified distance of one another.<br>
<code class="funcdef"><b class="fsfunc"><br>ST_DWithin</b>(</code><b style="color: rgb(255, 0, 0);">geometry</b> 
                                <var class="pdparam">g1</var>, <b style="color: rgb(255, 0, 0);">geometry 
                                </b><var class="pdparam">g2</var>, double precision 
                                <var class="pdparam">distance_of_srid</var><code>)</code>;<br><code class="funcdef"><b class="fsfunc">ST_DWithin</b>(</code><b style="color: rgb(255, 0, 0);">geography</b> 
                                <var class="pdparam">gg1</var>, <b style="color: rgb(255, 0, 0);">geography 
                                </b><var class="pdparam">gg2</var>, double precision 
                                <var class="pdparam">distance_meters</var><code>)</code>;<br><br>Could you explain me when we use <b>geometry </b>and when <b>geography</b>.<br>    Geometry which is a geometry tupe: POINT, LINE, POLYGON ... ?<br>    Geography: ...?<br>
    ...<br><br>Cheers.<br clear="all"><br>-- <br>Liem Nguyen<br>Developer<br>Axon Active Corp.<br>----------------------------------------------------------------------------<br>Direct Line      : +84 38 948 4645<br>Fax                  : +84 38 811 3489<br>
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