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OGR

This is an update to my previous post “WFS to PostGIS in 3 Steps”. Thanks to Even Rouault’s comments and improvements to GDAL, it is now possible to load Latin1-encoded WFS (like the one by data.wien.gv.at) into PostGIS in just one simple step.

To use the following instructions, you’ll have to get the latest GDAL (release-1600-gdal-mapserver.zip)

You only need to run SDKShell.bat to set up the environment and ogr2ogr is ready for action:

C:\Users\Anita>cd C:\release-1600-gdal-mapserver
C:\release-1600-gdal-mapserver>SDKShell.bat
C:\release-1600-gdal-mapserver>ogr2ogr -overwrite -f PostgreSQL PG:"user=myuser password=mypassword dbname=wien_ogd" "WFS:http://data.wien.gv.at/daten/geoserver/ows?service=WFS&request=GetFeature&version=1.1.0&typeName=ogdwien:BEZIRKSGRENZEOGD&srsName=EPSG:4326"

Thanks everyone for your comments and help!

This is just a quick “note to self” on some interesting information I picked up from the QGIS mailing list today. Kudos to David J. Bakeman for sharing this:

If both the input and the output arguments to ogr2ogr are directories then it will clip all of the shapes in the source directory and write them to the output directory.

So: ogr2ogr -clipsrc mask.shp output source

Shapefiles are the default so you don’t even need the -f “ESRI Shapefile”.

Foreword (added 2015-04-11)

There are two main options to load .csv files into QGIS

  • “Add delimited text layer” will guess the column data types. Use the “no geometry” option to load CSVs without coordinates.
  • “Add vector layer” by default interprets all columns as strings.

The following post describes how to change the default behavior of “Add vector layer”.

If you load .csv files through “Add vector layer”, all columns are interpreted as strings. That’s most likely not what you want, but it’s OGR’s default behaviour:

The OGR CSV driver returns all attribute columns with a type of string if no field type information file (with .csvt extension) is available.

Let’s create a .csvt file then!

The .csvt file has to have the same name as the .csv file it describes. (The same concept is used for Shapefiles.) It enables definition of the following data types: Integer, Real, String, Date (YYYY-MM-DD), Time (HH:MM:SS+nn) and DateTime (YYYY-MM-DD HH:MM:SS+nn).

A .csvt file contains only one line and the types for each column have to beĀ quoted and comma separated, e.g.

"Integer","Real","String"

You can even specify width and precision of each column, e.g.

"Integer(6)","Real(5.5)","String(22)"

Read more at: www.gdal.org/ogr/drv_csv.html

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