Integer field of CSV file always output as String when processed with ogr2ogr

Question

I have a file places.csv with the following contents:

name,lat,lon,type,population
Aalfang,48.8393882,15.0675236,village,410
Abern,48.0556773,13.1533381,village,203
Abersee,47.7266536,13.4169871,village,320
Abetzberg,48.0839721,14.76567,village,260
Abfaltersbach,46.7564042,12.5298515,village,616
Absam,47.2965003,11.5051409,village,6543
Abschlag,48.6241667,14.8638577,village,78
Absdorf,48.4001618,15.9803689,village,459

and an accompanying file places.csvt to specify the column types:

"String","CoordY","CoordX","String","Integer"

I am using ogr2ogr to filter the CSV file for entries in a spatial region with this command:

ogr2ogr -spat 12.0 47.0 15.0 49.0 -a_srs EPSG:4326 -oo X_POSSIBLE_NAMES=lon -oo Y_POSSIBLE_NAMES=lat places_filtered.csv places.csv

In the resulting CSV file, all values in the column population are represented as Strings with double quotes:

name,lat,lon,type,population
Abern,48.0556773,13.1533381,village,"203"
Abersee,47.7266536,13.4169871,village,"320"
Abetzberg,48.0839721,14.76567,village,"260"
Abschlag,48.6241667,14.8638577,village,"78"

How can I get ogr2ogr to output unquoted integer values for the integer field?

I tried many options, but no success. I haven't found a way to specify field/column types explicitly, besides supplying the .csvt file with equal name as the input file. Also the -oo AUTODETECT_TYPE=YES option gives the same result.

Answer 1

Read documentation from here https://gdal.org/drivers/vector/csv.html#layer-creation-options

STRING_QUOTING=[IF_NEEDED/IF_AMBIGUOUS/ALWAYS]: Defaults to IF_AMBIGUOUS. whether to double-quote strings. IF_AMBIGUOUS means that string values that look like numbers will be quoted (it also implies IF_NEEDED). Defaults to IF_AMBIGUOUS (behavior in older versions was IF_NEEDED)

Then do

ogr2ogr -spat 12.0 47.0 15.0 49.0 -a_srs EPSG:4326 -oo X_POSSIBLE_NAMES=lon -oo Y_POSSIBLE_NAMES=lat places_filtered2.csv places.csv -lco STRING_QUOTING=IF_NEEDED

more places_filtered2.csv
name,lat,lon,type,population
Abern,48.0556773,13.1533381,village,203
Abersee,47.7266536,13.4169871,village,320
Abetzberg,48.0839721,14.76567,village,260
Abschlag,48.6241667,14.8638577,village,78

Answer 2

Will be fixed in GDAL 3.8.2 per https://github.com/OSGeo/gdal/pull/8813

Answer 3

Using a VRT file?

• https://gdal.org/drivers/vector/vrt.html
• there is an example on the CSV page: https://gdal.org/drivers/vector/csv.html#building-point-geometries

I wrote a tutorial some years ago to explain a full example. It's in French but should be understandable with an automated translation: https://geotribu.fr/articles/2021/2021-09-07_traiter_fichiers_adresse_gdal_csv_vrt/