GDAL update issues - ObjectVision/GeoDMS GitHub Wiki

GeoDMS uses [GDAL]] 3 to read and write many vector and raster data formats, see [gdal.vect, gdalwrite.vect, gdal.grid and gdalwrite.grid.

This page lists known limitations of the GDAL based StorageManagers. Next to these, the limitations of the individual GDAL drivers themselves also apply.

writing in general

• When writing data to a file that is locked (e.g. a .dbf opened in MsExcel), no clear error dialog is presented. The error in the Detail Page reads like: gdal Error: error(1): %LocalDataDir%/gdalwrite_vect/gdal.dbf is not a directory, where a message like data can not be written as the resulting file is locked would be more informative.
• When writing a subitem structure, append the subitem name to the item names to avoid collisions of identical item names in the resulting file.

ESRI Shapefile

• Multiple geometries as subitems of one unit for which a StorageManager is configured are not supported, as it is undefined which geometry should be written to the .shp file and how the other geometries should be treated in the .dbf file. Configure at most one geometry per storage.

csv

• Null values and empty strings are represented the same in a written .csv file and become indistinguishable when the file is reread.

raster formats

• Sub-byte value types (bool, uint2, uint4): grid data can only be read from or written to a raster file if the number of bits per pixel in the file matches the number of bits of the [value type]], or if the file stores 8 bits per pixel and the value type is bool or uint4. Reading or writing uint2 data from/to an 8 bits per pixel raster file fails with an error like cannot convert 2 bits DMS data from 8 bits raster data. See also [Sub Byte Element.