Thread: pgsql2shp usage

Hello to all,

I downloaded an OSM map file namely "india.osm.bz2".
I transported it in PostgreSQL database "gis" with the command :

./osm2pgsql -m -d gis india.osm.bz2

The above command resulted in the creation of the following tables filled with data in database "gis"

gis=# \d
                 List of relations
 Schema |        Name        |   Type   |  Owner
--------+--------------------+----------+----------
 public | geometry_columns   | table    | anisha
 public | planet_osm_line    | table    | anisha
 public | planet_osm_point   | table    | anisha
 public | planet_osm_polygon | table    | anisha
 public | planet_osm_roads   | table    | anisha
 public | polygon_oid_seq    | sequence | postgres
 public | spatial_ref_sys    | table    | anisha

Now to convert the map data of one of the above tables in a shape file, I issued the following command:

pgsql2shp -f myfile gis planet_osm_line

Output:
Initializing... Warning, field addr:housenumber renamed to ADDR:HOUSE
Warning, field addr:interpolation renamed to ADDR:INTER
Warning, field admin_level renamed to ADMIN_LEVE
Warning, field construction renamed to CONSTRUCTI
Warning, field power_source renamed to POWER_SOUR
Done (postgis major version: 1).
Output shape: PolyLine
Dumping:

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

[126149 rows].

Question :
_______________________________________________________________________________________
How should I verify that the shape file resultant of the above command is a valid and uncorrupted one ?
_______________________________________________________________________________________

I am worried because the projection file namely "myfile.prj" contains the following !

PROJCS["WGS84 / Simple Mercator",GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS_1984", 6378137.0,
298.257223563]],PRIMEM["Greenwich", 0.0],UNIT["degree", 0.017453292519943295],AXIS["Longitude",
EAST],AXIS["Latitude", NORTH]],PROJECTION["Mercator_1SP_Google"],PARAMETER["latitude_of_origin",
0.0],PARAMETER["central_meridian", 0.0],PARAMETER["scale_factor", 1.0],PARAMETER["false_easting",
0.0],PARAMETER["false_northing", 0.0],UNIT["m", 1.0],AXIS["x", EAST],AXIS["y", NORTH],AUTHORITY["EPSG","900913"]]

The latitude/longitude values don't seem to be of India !!!!

Thanking you in anticipation,

Regards,
Anisha Kaul

-------------------------------------
Hi-Tech Gears Limited, Gurgaon, India

On Saturday 09 January 2010 19:03:59 Randall Thompson wrote:
> The Attribute Tables for a shape file are stored in .DBF format which has a
> restriction that field names are only ten characters long, so the warnings
> are simply informing you that those field names that are longer than 10
> characters are being truncated.  The projection definition indicates that
> the output spatial reference system (900913) is a variation of the Mercator
> projection which is used by Google Maps, Bing Maps, and other web map
> services.  So, these are not lat/long coordinates.
>
> Randall Thompson
> Castle Rock GIS
>
> ----------------------------------------

Many thanks to you for bothering to reply !

As you said that they are not the latitude/longitude coordinates, please guide me, if you can, that where should
I get the information regarding the projections w.r.t map of india stored in the shape file ?

--
Regards,
Anisha Kaul

-------------------------------------
Hi-Tech Gears Limited, Gurgaon, India