Web Mapping Illustrated

Name

Spatial Data Transfer Standard Files (SDTS)

Synopsis

This is a U.S. Geological Survey (USGS) format. SDTS has a raster and a vector format. The raster format isn't supported in MapServer; only the vector formats are supported, including VTP and DLG files.

File listing

SDTS files are often organized into state-sized pieces; for example, all pf the state of Maryland, U.S.A.

Files are also available for multiple types of features including hydrography, transportation, and administrative boundaries.

This example uses transportation data, which consists of 35 separate files, each with the suffix DDF.

    MDTRAHDR.DDF  MDTRARRF.DDF  MDTRCATS.DDF
    MDTRDQCG.DDF  MDTRFF01.DDF  MDTRLE02.DDF
    MDTRNA03.DDF  MDTRNO03.DDF  MDTRSPDM.DDF
    MDTRAMTF.DDF  MDTRBFPS.DDF  MDTRCATX.DDF
    MDTRDQHL.DDF  MDTRIDEN.DDF  MDTRLE03.DDF
    MDTRNE03.DDF  MDTRPC01.DDF  MDTRSTAT.DDF
    MDTRARDF.DDF  MDTRBMTA.DDF  MDTRDDSH.DDF
    MDTRDQLC.DDF  MDTRIREF.DDF  MDTRNA01.DDF
    MDTRNO01.DDF  MDTRPC02.DDF  MDTRXREF.DDF
    MDTRARDM.DDF  MDTRCATD.DDF  MDTRDQAA.DDF
    MDTRDQPA.DDF  MDTRLE01.DDF  MDTRNA02.DDF
    MDTRNO02.DDF  MDTRPC03.DDF

Data access/connection method

• SDTS access is available in MapServer through OGR.

• The CONNECTIONTYPE OGR parameter must be used.

• The path to the catalog file (????CATD.DDF) is required, including file extension.

• There are multiple layers in the SDTS catalog, some of which are only attributes and have no geometries.

ogrinfo examples

Here's an example that uses ogrinfo on a catalog file (note that the first seven layers don't have geometries):

                  > 
                  ogrinfo ...