[Gdal-dev] Updating Records Using OGR

[John Nipper]

Hello,

Just started using Ogr, and I am able to compile, run, and access data
without issue.  However, I am unable to change records.  It looks as though
it is built in, but I must be missing a step.  So here is what I do in
simplified C++ ... much of which is copied from ogrinfo.cpp.  Note, that I
have omitted all error checking code from the following code:

OGRRegisterAll();

OGRDataSource *poDS;

OGRSFDriver *poDriver;

poDS = OGRSFDriverRegistrar::Open( pszDataSource, TRUE, &poDriver );  //
Where pszDataSource is set to the datasource

poResultSet = poDS->ExecuteSQL( pszSQLStatement, poSpatialFilter, NULL );
// and pszSQLStatement is set as well

OGRFeature *poFeature;

OGRErr retError;

retError = poLayer->StartTransaction();

while( (poFeature = poResultSet->GetNextFeature()) != NULL )

{

    // Do some thing to the geometry and/or features

    //For example

    nameFld = poFeature->GetFieldIndex("NAME");

    poFeature->SetField(nameFld, featName2);  // Where featName2 is a new
string to place in the field value.

    poFeature->SetFeature(poFeature);

}
retError = poLayer->CommitTransaction();


I tried the above scenario with shapefiles as well as Oracle Spatial.  I can
loop through the data within the debugger, and everything looks all good.
But any information that I change, never gets posted in the original data.
I must be doing something wrong, or leaving out something.  If I am reading
the driver code correctly, the data should be replaced.

Thanks,

John Nipper
jnipper at bhinc.com