topic Re: UpdateCursor error: fields size must match size of the row in Python Questions

UpdateCursor error: fields size must match size of the row

JustinMuldowney — Sat, 20 Jul 2024 23:23:54 GMT

Using Pyscripter to take the last 5 characters (the ZIP code) of an address field and putting that into a separate field.

I am getting the following error:

File "C:\Users\battl\Desktop\experiment.py", line 21, in <module>
zipCursor.updateRow([zipRow])
TypeError: fields size must match size of the row

When I google it, it's saying that the zipRow at the end needs to be designated as a list (thus the square brackets, it doesn't work with or without them)

Here's my code:

import arcpy

arcpy.env.workspace = r"C:\GIS\VoteTally"

gdbTable = "\\Voters.gdb\\voterRecords"

addressField = "RESIDENTIAL_ADDRESS__CITY_STATE_ZIP"

zipField = "ZIP"

with arcpy.da.UpdateCursor (gdbTable, (addressField, zipField)) as zipCursor:

for zipRow in zipCursor:

street = zipRow[0]

zipCode = street[-5:]

zipRow = zipCode

zipCursor.updateRow([zipRow])

Any help would be greatly appreciated.

Re: UpdateCursor error: fields size must match size of the row

DanPatterson — Sun, 21 Jul 2024 01:11:09 GMT

Re: UpdateCursor error: fields size must match size of the row

Luke_Pinner — Sun, 21 Jul 2024 01:18:44 GMT

You're reading in two fields and returning (updating) one.You need to pass the same number and order of fields back to updateRow, even if you're not actually changing all of them.

with arcpy.da.UpdateCursor (gdbTable, (addressField, zipField)) as zipCursor: for zipRow in zipCursor: street = zipRow[0] zipCode = street[-5:] zipRow = [street, zipCode] zipCursor.updateRow(zipRow)

Re: UpdateCursor error: fields size must match size of the row

JustinMuldowney — Sun, 21 Jul 2024 15:15:25 GMT

That fixed the error I was seeing. It was then saying that street[-5:] was a None Type. When the table is created, it randomly added a completely Null row at 27096 (there's 140k). So it was getting tripped up there. I added a If row[0] is None delete row and it now works.
I also had to edit your line 5 to zipRow[1] = zipCode. The way you had it basically just copied the full street address into the zip field.

Thank you for the assist!

Re: UpdateCursor error: fields size must match size of the row

Luke_Pinner — Mon, 22 Jul 2024 10:25:28 GMT

@JustinMuldowney wrote:
...
I also had to edit your line 5 to zipRow[1] = zipCode. The way you had it basically just copied the full street address into the zip field.

No, that would do exactly the same as what I wrote, it would return the original street address in the first element and the zip code in the second.

e.g.

zipRow = ["abc 12345", None] # Some dummy data street = zipRow[0] zipCode = street[-5:] zipRow[1] = zipCode print(zipRow == [street, zipCode]) True

Re: UpdateCursor error: fields size must match size of the row

HaydenWelch — Tue, 23 Jul 2024 01:55:02 GMT

To add to this, always declare your field list/tuple as a single variable. If you are doing read and update operations and have to change a field it can become a nightmare if you forget to update the field order or field names somewhere down the line.

**cursor_fields = (addressField, zipField)**

Then use that anywhere that you need those specific fields accessed.