Use Unsplit Lines instead of Dissolve for 3D lines
Executing: Dissolve Lines_3d D:\x\clipped.gdb\Lines_3d_dissolved nid # SINGLE_PART UNSPLIT_LINES
Start Time: Tue Jan 19 10:36:18 2016
ERROR 999999: Error executing function.
The Geometry has no Z values
Failed to execute (Dissolve).
Failed at Tue Jan 19 10:36:19 2016 (Elapsed Time: 0.44 seconds)
…a better method is to run Unsplit Line and dissolve by the required feature classes. The Unsplit Line method allows 3D features to remain 3D which is crucial. The Dissolve method requires the user to convert the 3D features to 2D then bring those features back to 3D.
Sigh, why doesn’t Dissolve say something when the input is a 3D line?