Check in all tables in database if two fields are not null, with ArcPy?

Question

I would like to check two fields in each tables which name start with X_ into a database !

I've started to write something like :

arcpy.env.workspace = "C:/myWorkspace.sde"
tables = arcpy.ListTables("X_*")
for table in tables:
 print(table)

But now I'm stuck for searching into the tables if there is Field_A and Field_B only filled with NULL values

Answer 1

Use the da.SearchCursor to create a list of all entries then check list:

import arcpy
arcpy.env.workspace = "C:/myWorkspace.sde"
tables = arcpy.ListTables("X_*")
for table in tables:
 all_rows = []
 with arcpy.da.SearchCursor(table, ['FieldA','FieldB']) as cursor:
 for row in cursor:
 all_rows.extend(row)
 if all_rows.count(None) == len(all_rows):
 print('{0} is all none'.format(table))

• Emil Brundage: all_rows.count(None) will always return 0 because there are no None values in the list. Instead there will be a tuple (None, None) for all-None rows.
• Bera: With append that would be true, not with extend
• Emil Brundage: ah my mistake. I always use append.

Answer 2

@BERA has a good answer but it can be made more efficient by skipping the creation of lists and by breaking the iteration of the cursor if a value is found.

import arcpy
arcpy.env.workspace = "C:/myWorkspace.sde"
tables = arcpy.ListTables("X_*")
for table in tables:
 vals = False
 with arcpy.da.SearchCursor(table, ['FieldA','FieldB']) as cursor:
 for row in cursor:
 if row [0] != None or row [1] != None:
 print ("{} fields are not null".format (table))
 vals = True
 break
 if not vals:
 print ("{} fields are null".format (table))

Answer 3

Thanks a lot for your help both of you ! I finally done something like that :

import arcpy
arcpy.env.workspace = "C:/myWorkspace.sde"
tables = arcpy.ListTables("X_*")
emptyTables = []
print "--- Tables where fields Field_A or Field_B are empty or null :"
for table in tables:
 vals = False
 with arcpy.da.SearchCursor(table, ['Field_A', 'Field_B']) as cursor:
 for row in cursor:
 if row[0] == 'NULL' or row[0] == None or row[1] == 'NULL' or row[1] == None :
 print table
 vals = True
 break
 if not vals:
 emptyTables.append(table)
print "------------------"
print "--- Empty Tables :"
for emptyTable in emptyTables:
 print emptyTable