Calculate field finishes but a portion of the records now contain null values in the field, is there a limit?
How many rows are calculated? for many Feature Services the maximum number of rows that can be returned by the query is defined in the service. ESRI default is 1000 rows.
To test, in Python suggest you do a loop or add code to 'chunk' the calculation by OBJECT ID or FID (i.e., calc FID 0 to 999 then repeat for 1000-1999, until your done. Then check and see if the null has been solved.
Could be an issue with the formula you used.
For example, if you have an if statement and don't provide an explicit else option, it will assume that the "Else" is None.
calc(!Field1!)
def calc(field1):
if "a" in field1:
return "Road"
But if you give it an Else, it does fine. This example returns the current value if the "if" doesn't match.
calc(!Field1!, !Field2!)
def calc(field1, field2):
if "a" in field1:
return "Road"
else:
return field2
Maybe I'm misunderstanding, but I think it's the same issue regardless.
In this example, I've joined the destination table to the origin table based on the "joinField" field. I want to populate the "ValueToPopulate" field in the origin table with values from the "ValueToCopy" field in the destination table.
There are 6 records in the origin table and 5 in the destination table. The 6th record in the origin table, which is affected by the join, already has a value in the field I want to populate.
I perform the join.
Then I open the Field Calculator and input the following:
!origTable.ValueToCopy!
And hit apply
My value in pre-populated row was overwritten with null.
To solve this, you have two primary options:
1) Use a codeblock with an if statement, as detailed in my earlier post
2) Select the records you want to populate via eitherof these two methods:
- Definition Query ("ValueToPopulate is Null")
- Select by Attributes/ Manual Selection
Field Calculator will only operate on what's present or selected (Selection takes priority).
