Allow fields that are null when there's an associated default value.
This can be used for drivers where the low-level layers will automatically set the
field value to the associated default value.
This flag only makes sense if OGR_F_VAL_NULL is set too.
Used by OGR_F_Validate().
@since GDAL 2.0
Allow fields that are null when there's an associated default value. This can be used for drivers where the low-level layers will automatically set the field value to the associated default value. This flag only makes sense if OGR_F_VAL_NULL is set too. Used by OGR_F_Validate(). @since GDAL 2.0