[gdal-dev] Why are fields required in osmconf.ini file?

[Even Rouault]

Le jeudi 17 novembre 2016 22:20:02, Djordje Spasic a écrit :
> Hello,
> 
> When converting an .osm file to .shp files with ogr2ogr.exe, one needs to
> define a list of required fields (keys) in gdal-data\osmconf.ini file, for
> each geometry type (points, lines, multipolygons, multilinestrings).Like
> so (labelled in red color): [points]#common
> attributesosm_id=yesosm_version=noosm_timestamp=noosm_uid=noosm_user=noosm
> _changeset=no #keys to report as OGR
> fieldsattributes=name,barrier,highway,ref,address,is_in,place,man_made Why
> is that so? Why do field names need to be predefined before their
> extraction from the .osm file?
> 
> Why can't only those fields which already exist in the .osm file, be
> extracted?

That would require doing 2 read passes of the file to determine which fields 
exist. There's no header mentionning which fields are used. The whole file has 
to be read.

> 
> 
> Thank you for the reply.
> 
> Kind regards,
> Djordje Spasic

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