Change text values to NULL using update cursor

tigerwoulds — Sun, 03 Mar 2024 23:23:07 GMT

I am trying to write a script that will take different permutations of the word Null and convert them to true database Nulls. I have users populate 'Null', 'NULL' or similar, and I need to convert these to true Nulls.

I have a list of the different permutations and a geodatabase with several feature classes. I'm trying to loop through my list and compare against all string values in all feature class. If there is a match, convert the string to the true Null.

I am getting an invalid syntax error on line 26:

row = [None if i in nullList else pass for i in row]

If I replace pass with print ('Test') it changes every value to Null. Any ideas?

import arcpy import os import time inputGDB = r'C:\Test_null.gdb' # Set workspace to input GDB arcpy.env.workspace = inputGDB nullList = ['', ' ', ' ', ' ', '-', '--', '---', '<Null>', '<NULL>', 'Null', 'NULL', '”Null”', '”NULL”'] datasets = arcpy.ListDatasets(feature_type='feature') datasets = [''] + datasets if datasets is not None else [] # Loop through all feature classes print('Reading Feature Classes...') for ds in datasets: for fc in arcpy.ListFeatureClasses(feature_dataset=ds): # Build a list of all TEXT/String Fields where NULL values are allowed fieldList = [i.name for i in arcpy.ListFields(fc) if i.type == 'String' and i.isNullable is True] # Iterate through each row and execute the clean with arcpy.da.UpdateCursor(fc, fieldList) as cursor: for row in cursor: row = [None if i in nullList else pass for i in row] cursor.updateRow(row) print('Done.')

Re: Change text values to NULL using update cursor

DanPatterson — Thu, 24 Feb 2022 00:30:47 GMT

row = ['', 'a', ' ', ' ', ' ', '-', '--', '---', '<Null>', '<NULL>', 'Null', 'NULL', '”Null”', '”NULL”'] nullList = ['', ' ', ' ', ' ', '-', '--', '---', '<Null>', '<NULL>', 'Null', 'NULL', '”Null”', '”NULL”'] [None if i in nullList else pass for i in row] File "<ipython-input-7-9b1bf3f7cd3e>", line 1 [None if i in nullList else pass for i in row] ^ SyntaxError: invalid syntax # -- no pass [None if i in nullList else i for i in row] [None, 'a', None, None, None, None, None, None, None, None, None, None, None, None]

Re: Change text values to NULL using update cursor

tigerwoulds — Thu, 24 Feb 2022 01:03:27 GMT

Thanks! Replacing pass with i did the trick.

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Change text values to NULL using update cursor

Re: Change text values to NULL using update cursor

Re: Change text values to NULL using update cursor