[gdal-dev] RFC 29: OGR Set Desired Fields

[Martin Dobias]

On Wed, Jul 21, 2010 at 1:36 PM, Jez Walters <Jez.Walters at ipl.com> wrote:
> Although I take your point about the interface not affecting ogr2ogr, surely the potential speed boost is worth extending to this utility too - or would that be a separate ticket?  I for one would welcome improving the performance of ogr2ogr using the approach you have suggested - when I launch the current trunk development version of ogr2ogr from VBScript it gets stuck in an infinite loop trying to process a 5x5km vector data chunk.

ogr2ogr could probably use the API when "-select" option is used - to
ignore fields which are not being requested. Any other performance
improvements are unrelated to this RFC.


> This issue aside, won't the fact that field names are constant but field numbers are not in the OS MasterMap vector data present problems for those that wish to programmatically parse the OS GML using your interface?

AFAIK once a layer gets open, the indexes of fields for this layer stay fixed.

Regards
Martin