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<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>Hi all,
</FONT></SPAN></DIV>
<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>I am new to PostGIS
and I have installed it onto an existing PostgreSQL database. I have a table
with an x and a y column and want to make a point geometry from these columns.
</FONT></SPAN></DIV>
<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>I have done the
following</FONT></SPAN></DIV>
<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>SELECT
AddGeometryColumn('table_xy_45700522','xypoint',-1,'POINT',1);</FONT></SPAN></DIV>
<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>ALTER TABLE
table_xy_45700522 DROP CONSTRAINT enforce_dims_xypoint; - needed because
it seemed to fail otherwise?</FONT></SPAN></DIV>
<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>and now have a table
which looks like </FONT></SPAN><SPAN class=039584118-09082005><FONT face=Arial
size=2>samplename (varchar), x(float8), y(float8), xypoint(geometry). There are
800+ records in the table all with values in the samplename, x and y columns.
How can I use MakePoint or some other function to get the geometry for each of
these points? (this is a test table - the real table has considerably more
points)</FONT></SPAN></DIV>
<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>Looking through the
archives I only see references to loading the data from an external
file.</FONT></SPAN></DIV>
<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>Thanks for any
assistance.</FONT></SPAN></DIV>
<DIV><SPAN class=039584118-09082005><FONT face=Arial size=2>Robyn
Rennie</FONT></SPAN></DIV>
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