Two things I noticed right off the bat:
1) You are trying to assign values to the row returned by the cursor which is an immutable tuple
with arcpy.da.UpdateCursor(facilities_layer, update_fields) as cursor:
for row in cursor:
...
if facility_data:
...
row[1] = facility_data.get("FACILITYNA", "")
...
To get around this, you can cast the row to a list at the beginning of the cursor:
with arcpy.da.UpdateCursor(facilities_layer, update_fields) as cursor:
for row in cursor:
row = list(row)
...
if facility_data:
...
row[1] = facility_data.get("FACILITYNA", "")
...
or even better (assuming you know the field names and aren't relying on a structured record), you can make it a dictionary:
with arcpy.da.UpdateCursor(facilities_layer, update_fields) as cursor:
for row in cursor:
row_dict = dict(zip(cursor.fields, row))
...
if facility_data:
...
row_dict['NAME'] = facility_data.get("FACILITYNA", "")
...
cursor.updateRow(tuple(row.values()))
Be careful with this one as you can't just pass row back to the update, you need to convert your dictionary values to a new row. This does require your dictionary to be ordered though, which is the default as of 3.7 and an official language feature (arcpy uses 3.12 now I believe? So you should be fine)
2) You are doing too much work inside the UpdateCursor
This is more of a code smell than anything. UpdateCursors maintain database locks, so you are tying up the target database with a cursor for the duration of your operation. Ideally you would build the update dictionary using a SearchCursor, then apply the updates all at once using UpdateCursor:
# Use a dictionary comprehension to map rows to an id key
records = {
row[0] : row
for row in arcpy.da.SearchCursor(fc, fields, where_clause='<CLAUSE>', spatial_filter=Geometry())
}
# Initialize an update dict
updates: dict[int, tuple[Any, ...]] = {}
for rec_id, rec in records:
# Do your row processing here
updates[rec_id] = rec
with arcpy.da.UpdateCursor(fc, fields, where_clause='<CLAUSE>', spatial_filter=Geometry()) as cursor:
for row in cursor:
# use the index of your key field here, or use the dictionary trick I showed before
rec = update.get(row[0])
if rec:
cursor.updateRow(rec)
In this example, the two cursors are only locking the database for as long as it takes to traverse them. All lengthy operations are now being done in Python/memory
I'm pretty sure that point one is the source of your cursor error though, you can pretty easily fix that by casting row to a list. I would definitely recommend you think about implementing some of the patterns in point 2 though. Debugging a big script like this that isn't typed and uses magic numbers for indexes can be an absolute pain. Especially when it's not failing, but giving incorrect/inconsistent results.
