Error when updating arcpy.SearchCursor to arcpy.da.SearchCursor

Question

I'm trying to update a python script to use the arcpy.da.SearchCursor instead of the legacy arcpy.SearchCursor. The cursor searches for duplicate values in a field.

I am getting an error:

Traceback messages below.
AttributeError: 'tuple' object has no attribute 'getValue'

There must be a syntax difference between the two cursors that I have wrong. Can anyone tell where I am going wrong?

#Constant Vars
dblayerprefix = "CityworksGIS_Test.DBO."
whydrant = dblayerprefix + "WHYDRANT"
#Parent
centralDB ="<YOUR DB CONNECTION>" #this variable used for replication
#Child
editDB ="Database Connections/DBO@CityworksGIS_Test.sde"
columnName = 'AssetID'
updateSql = "AssetID IS NULL"
noNullSql = "AssetID IS NOT NULL"
#old variable for arcpy.searchcursor
fieldascend = columnName + " A"

try:
    #Set editor environment workspace
    arcpy.env.workspace = 'Database Connections/DBO@CityworksGIS_Test.sde'

    #Old cursor:
    #rows = arcpy.SearchCursor('CityworksGIS_Test.dbo.WHYDRANT', noNullSql ,"","", fieldascend)
    #New cursor
    rows = arcpy.da.SearchCursor('CityworksGIS_Test.dbo.WHYDRANT', columnName, noNullSql, sql_clause=(None, 'ORDER BY ASSETID ASC'))
    dupValuesList = [] #List for holding empty values
    print 'Checking WHYDRANT for duplicate SampleID values'
    i = -1
    row = rows.next()
    value = row.getValue(columnName)
    for row in rows:
        if row.getValue(columnName) != value:
            value = row.getValue(columnName)
        else:
            dupValuesList.append(value)

    #Check duplicates and create report
    if len(dupValuesList) == 0:   
        print 'No duplicates found moving on'  
        del rows
        del dupValuesList
    else:
        raise ValueError('Duplicate AssetID values found in WHYDRANT')

Answer 1

If I understand what your original code was doing, you are looking for duplicate ID values in your AssetID column. This modification of your Search Cursor will create a python Set to store all AssetID values, and before it stores each one it will check if the ID already exists in the set. If it does exist then it's a duplicate, and so is written to the dupValuesList List.

#New cursor
dupValuesList = [] # List for holding duplicated IDs
assetIDSet = set() # Set to record all IDs
print 'Checking WHYDRANT for duplicate AssetID values'
with arcpy.da.SearchCursor('CityworksGIS_Test.dbo.WHYDRANT', columnName, noNullSql) as cursor:
    for row in cursor:
        if row[0] in assetIDSet:
            dupValuesList.append(row[0])
        else:
            assetIDSet.add(row[0]) 

#Check duplicates and create report