How do you know what SRID to use for a shp file?
geodjango, gis, postgis, srid
Solution
To elaborate on synecdoche's answer, the SRID is sometimes called an "EPSG" code. The SRID/EPSG code is a defacto short-hand for the Well-Known-Text representations of projections.
You can do a quick search on the SRID table to see if you can find an exact or similar match: `SELECT srid, srtext, proj4text FROM spatial_ref_sys WHERE srtext ILIKE '%BLAH%'`
Above was found at http://www.bostongis.com/?content_name=postgis_tut01.
You can also search on spatialreference.org for these kinds of things. The search tool is primitive so you may have to use a Google search and specify the site, but any results will show you the ESRI PRJ contents, the PostGIS SQL INSERT, and a bunch of other representations.
I think your PRJ is at: http://spatialreference.org/ref/sr-org/15/
Problem
I am trying to put a SHP file into my PostGIS database, the the data is just a little off. I think this is because I am using the wrong SRID. The contents of the PRJ file are as follows: ``` GEOGCS["GCS_North_American_1983", DATUM["D_North_American_1983", SPHEROID["GRS_1980",6378137.0,298.257222101]], PRIMEM["Greenwich",0.0], UNIT["Degree",0.0174532925199433]] ``` What SRID does this correlate to? And more generally, how can I look up the SRID based on the information found in the PRJ file? Is there a lookup table somewhere that lists all SRID's and their 'geogcs' equivalents? The data imported using `srid=4269` and 4326 were the exact same results. Does this mean I'm using the wrong SRID, or is this just expected margin of error? The shp file is from here.