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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m a postgis beginner and I hope the list can bear
with me as I ask some newbie questions.</span></font></p>
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font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>My current questions are all about the SRID.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Is there a more human-readable table that contains the SRIDs
and descriptions?</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Are the SRIDs always the same? For example, SRID 2959 on
my system is UTM zone 18 with the GRS80 ellipse. Is this always SRID 2959
for everybody?</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The documentation includes this example:</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<pre><font size=2 face="Courier New"><span style='font-size:10.0pt'>CREATE TABLE parks ( PARK_ID int4, PARK_NAME varchar(128), PARK_DATE date, PARK_TYPE varchar(2) );</span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>SELECT AddGeometryColumn('parks', 'park_geom', 128, 'MULTIPOLYGON', 2 );</span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'> </span></font></pre><pre><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>This column has an SRID of 128? Does this mean that only objects with SRID=128 can be inserted in the column? I thought you included an SRID when you INSERT an object?</span></font></pre><pre><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'> </span></font></pre><pre><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>How does postgis use the SRID internally? Can it properly compare an object with one SRID with an object with a different SRID?</span></font></pre><pre><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'> </span></font></pre><pre><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>Finally, if I have missed some documentation that explains this, please point me in that direction!</span></font></pre>
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font-family:Arial'> </span></font></p>
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