UpdateCursor cannot see new field added to feature class

Question

I needed to add a new field to a feature class to act as a unique key, but when I run:

fields = ['OID@', 'state', 'navkey']
ids = inspected_points #list of oid values
oidfield = arcpy.Describe(points).OIDFieldName #reference to ObjectID field name

where_clause_points = """{0} IN{1}""".format(arcpy.AddFieldDelimiters(points, oidfield),tuple(ids))    

with arcpy.da.UpdateCursor(points, fields, where_clause_points) as cursor:

I get the error:

for row in cursor:
RuntimeError: Attribute column not found [42S22:[Microsoft][ODBC Driver 13 for SQL Server][SQL Server]Invalid column name 'navkey'.] [db.DBO.lines_split][STATE_ID = 0]

I have been able to add and write to other fields, so I'm not sure why this one is not working. I know the field is there and available:

fields = arcpy.ListFields('lines_split')
    for field in fields:
    print(field.name)

This produces:

ProjectId
SurveyId
TechnicianUsername
TimestampUTC
GPSLatitude
GPSLongitude
GPSAccuracyInFeet
GPSAltitudeInFeet
Shape
OBJECTID
state
NEAR_FID
NEAR_DIST
NEAR_X
NEAR_Y
navkey

This field is just a text field. I just want to populate it with values, but cannot for some reason access it. The code above all works perfect if you remove the 'navkey' from the list of fields, but once you add it in it fails.

Ultimately I am looking to create and populate a field to contain GUIDS and act as a unique key, since you cannot rely on ObjectID or GlobalID as they can change and CopyFeatures does not copy the same keys. I have the python code to generate GUIDS as a string, but I need access to this new field to populate them.

Answer 1

With the assistance of smiller, I was able to get that new field populated with the GUID values:

fields = ['OID@', 'state', 'navkey']
ids = inspected_points #list of oid values
oidfield = arcpy.Describe(points).OIDFieldName #reference to ObjectID field name
where_clause_points = """{0} IN{1}""".format(arcpy.AddFieldDelimiters(points, oidfield),tuple(ids))    

with arcpy.da.UpdateCursor(points, fields, where_clause_points) as cursor:
    for row in cursor:
        pk = str(uuid.uuid4()) #generate a GUID
        row[2] = pk
        cursor.updateRow(row)

I actually added code at the beginning of my code that may have resolved this (possibly incorrectly worded/misleading) error:

where_clause = "[navkey] = '<Null>'"
field = ['navkey']

with arcpy.da.UpdateCursor(points, field, where_clause) as cursor: 
    for row in cursor:
        pk = str(uuid.uuid4())
        row[0] = pk
        cursor.updateRow(row)

This populated that new field with the generated GUID values, as strings, with no attribute could not be found error.