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<body class='hmmessage'><div dir='ltr'><pre><font style="font-size: 10pt;" size="2">Dear community:<br><br>I</font><font style="font-size: 10pt;" size="2"> am about to finish up issue #329, </font><font style="font-size: 10pt;" size="2"><font style="font-size: 10pt;" size="2">Incremental Create Topology</font><br><br> Actually </font><font style="font-size: 10pt;" size="2">John Zabrenski mailed to user's list on june last year, and he tested the solution,<br> but the merge remained pending.<br><br>The actual signature of the function is:<br><br></font><font style="font-size: 10pt;" size="2"><br></font><font style="font-size: 10pt;" size="2"><font style="font-size: 10pt;">CREATE OR REPLACE FUNCTION pgr_createtopology(edge_table text, tolerance double precision,
the_geom text default 'the_geom', id text default 'id',
source text default 'source', target text default 'target',rows_where text default 'true')<br><br>the minimal usage is like this: (I like defaults... less typing) <br></font></font><font style="font-size: 10pt;" size="2"><font style="font-size: 10pt;"><font style="font-size: 10pt;"><font style="font-size: 10pt;">pgr_createtopology(edge_table, tolerance)</font></font><br></font>And this will delete any topology information already stored in edge_table, if any.<br><br></font><font style="font-size: 10pt;" size="2"><br></font><font style="font-size: 10pt;" size="2">I am about to add a flag "clean", so I am asking what is de preferred default value for the flag?</font><font style="font-size: 10pt;" size="2"><br></font></pre><div id="_messageId611191527" data-rid="20568786" data-mid="611191527" class="_message chatTimeLineMessage chatTimeLineMessageAnim clearfix chatTimeLineMessageMine"><div class="_chatTimeLineMessageBox chatTimeLineMessageInner"><div class="chatTimeLineMessageArea clearfix"><pre><font style="font-size: 10pt;" size="2"><br>CREATE OR REPLACE FUNCTION pgr_createtopology(edge_table text, tolerance double precision,
the_geom text default 'the_geom', id text default 'id',
source text default 'source', target text default 'target',rows_where text default 'true',
clean boolean default true) <<<<<<</font></pre></div></div></div><div class="chatTimeLineMessageArea clearfix"><pre><font style="font-size: 10pt;" size="2">
CREATE OR REPLACE FUNCTION pgr_createtopology(edge_table text, tolerance double precision,
the_geom text default 'the_geom', id text default 'id',
source text default 'source', target text default 'target',rows_where text default 'true',
clean boolean default false) <<<<<<</font></pre></div><font style="font-size: 10pt;" size="2">My personal preference is clean = False (Don't clean), that is, it will continue with the topology where source & target values are null</font><font style="font-size: 10pt;" size="2">. That way if I add 100 rows to my 25million edges table, it will just add the topology for those 100 rows and not delete the existing topology and restart constructing the topology of 25million +100 edges.</font><br><br>Please, feedback.<br><br> </div></body>
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