Just to close this out I'll reply to my own post. I had been performing edits without initiating an edit session in the script. Instead I started editing manually (Edit menu -> Start Editing), and then started the script. This works without problems on an unversioned file GDB, but on a versioned SDE it fails. The solution was to start the edit session within the script (and NOT start editing manually prior to starting the script). See this Esri page for details: Editor (arcpy.da) (Note: as of Apr 9, 2013 this page has a typo in example 2 at the bottom: the startEditing and startOperation call order is reversed, it should be startEditing first and then startOperation).Some additional notes: To run this from an active ArcMap session you need to get the edit layer's workspacePath. For reasons I still don't understand if I change the version of a layer in the source tab of the Table of Contents the layer loses its workspacePath value. Creating a database connection to your version of the SDE and loading layers from there seems to mitigate this issue (since you don't have to change the version). Thus the pertinent code is as follows:import arcpy, os layerName = arcpy.GetParameterAsText(0) # Set script parameter as type Feature Layer mxd = arcpy.mapping.MapDocument("CURRENT") # assuming one data frame layer = arcpy.mapping.ListLayers(mxd, os.path.basename(layerName))[0] # basename strips off a ToC group(s) edit = arcpy.da.Editor(layer.workspacePath) # Need to make sure workspacePath is being populated edit.startEditing(False, True) edit.startOperation() # [...] cursor operations, data writing, updateRow calls here edit.stopOperation() edit.stopEditing(True)
