Thanks Mark. This gives me a direction to go. I have the correct SRS, and your other points are valuable. ST_GeomFromText is really what I was missing. Thanks.<br><br>The fact that I have two data tables to combine, would a View help here? Or somehow modify the SELECT statements that would go into the ST_GeomFromText function? (the examples only show hard-coded coordinates but I'm hoping a SELECT statement can provide input.)<br>
<br>- John<br> <br><br><br><div class="gmail_quote">On Tue, Jan 18, 2011 at 4:20 PM, MarkW <span dir="ltr"><<a href="mailto:mark.wimer@gmail.com">mark.wimer@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
Now that you have data in columns in Postgresql, you can use SQL statements to create your spatial data. Here are the steps:<br>1) identify your SRID/ spatial reference system<br>2) create geometries by passing your x and y with a spatial ref to the right function, and <br>
3) add a row to the geometry_columns table so that other applications can more easily see the spatial data. <br><br>1) It's much easier if you can match your coordinate system to the right UTM srids in the spatial_ref_sys table; see <a href="http://spatialreference.org" target="_blank">spatialreference.org</a> for help.<br>
2) See this function:<br><a href="http://www.postgis.org/docs/ST_GeomFromText.html" target="_blank">http://www.postgis.org/docs/ST_GeomFromText.html</a><br>(and to prove it works, the reverse is ST_X or ST_Y) to get X,Y back out )<br>
3) <a href="http://postgis.refractions.net/docs/ch04.html#Manual_Register_Spatial_Column" target="_blank">http://postgis.refractions.net/docs/ch04.html#Manual_Register_Spatial_Column</a><br>
(but also see the help under 'AddGeometryColumn (<a href="http://postgis.refractions.net/docs/AddGeometryColumn.html" target="_blank">http://postgis.refractions.net/docs/AddGeometryColumn.html</a>)<br><br>Hope this helps. <br>
<br>Mark<br>
<br><br><div class="gmail_quote"><div><div></div><div class="h5">On Tue, Jan 18, 2011 at 3:37 PM, John Callahan <span dir="ltr"><<a href="mailto:john.callahan@udel.edu" target="_blank">john.callahan@udel.edu</a>></span> wrote:<br>
</div></div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div><div></div><div class="h5">
I apologize for asking what seems like an easy question. I'm really just getting started with PostGIS and not sure which way to go here. I have a two tables in MS Access format. They are:<br><br>Table1: StationID, easting, northing, elevation, etc...<br>
Table2: StationID, data values...<br><br>Table1 is basically an inventory of all our stations. Table2 is a subset that includes only stations we have certain data for. How would I convert these into a point data set (of Table2 stations) in PostGIS? I was able to copy the tables from Access into Postgres. Where would I go from here? Maybe OGR would help going directly from Access (or text exports of Access) into PostGIS? <br>
<br>I am using Postgres 9.0.2/PostGIS 2.0.0 on Windows, and using Quantum GIS for viewing. Thanks for any guidance.<br><br>- John<br><br clear="all">**************************************************<br><font color="#888888">John Callahan, Research Scientist<br>
Delaware Geological Survey, University of Delaware<br>URL: <a href="http://www.dgs.udel.edu" target="_blank">http://www.dgs.udel.edu</a><br>**************************************************<br>
</font><br></div></div></blockquote></div>
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