topic Re: Search Cursor - Search Entire Row? in Python Questions

Search Cursor - Search Entire Row?

BenYoungs — Tue, 06 Sep 2011 20:38:17 GMT

All,

This may be an obvious question but I am having a little trouble with this... I am writing a script to loop through all the feature classes in a given workspace, and I need to search all fields (or all string fields, at minimum) in each feature class based on a provided string.

Essentially, I need to do what the 'Find' command in ArcMap is supposed to do, except I need to run this automatically on hundreds or potentially thousands of feature classes.

I have been playing around with a Search Cursor to do this, but I havent been able to iterate through each field for every row of the table successfully.

I am sure I could call the 'Select by Attributes' tool in Python and re-run that tool for each field in the feature class, but that seems inefficient to me.

Has anyone done anything like this before? Am I over-thinking this one and there is a simple solution?

I am using 9.3.1 in this instance but could write it for 10 if necessary. Thanks in advance.

Re: Search Cursor - Search Entire Row?

DarrenWiens2 — Tue, 06 Sep 2011 21:44:43 GMT

Inside your SearchCursor loop, you should be able to loop through each field (or limit to string fields) with ListFields to test the value against your string. I have no idea if this is the fastest method or not.

Re: Search Cursor - Search Entire Row?

BenYoungs — Wed, 07 Sep 2011 13:53:14 GMT

Inside your SearchCursor loop, you should be able to loop through each field (or limit to string fields) with ListFields to test the value against your string. I have no idea if this is the fastest method or not.

That was the first thing I tried. The problem that I was having was looping through each field for every row of the table:

for field in fieldlist:
if row.field == searchstring
# do something

When I run this I get the following error:

'Row: Field field does not exist'

So I can't use the field variable with the row. statement to search for a value. I'm not sure how I can get around that.

Re: Search Cursor - Search Entire Row?

DarrenWiens2 — Wed, 07 Sep 2011 14:27:19 GMT

I think you need to use getValue and setValue to work with field names as variables (not sure though).

Re: Search Cursor - Search Entire Row?

LeighHolcombe — Sat, 11 Dec 2021 14:10:40 GMT

I think this is what you're looking for. This is a simple find and replace routine that will loop through every field of every row in your shapefile/feature class and make the necessary changes.

x = the value you want to find
y = the value you want to replace it with
filename = the file you're working on

rows = arcpy.UpdateCursor(filename)
fields = arcpy.ListFields(filename)
for row in rows:
    for field in fields:
        value = row.getValue(field)
        if value == x:
            row.setValue(field,y)
            rows.updateRow(row)

Hopefully, that at least gets you pointed in the right direction.

Re: Search Cursor - Search Entire Row?

BenYoungs — Wed, 07 Sep 2011 17:32:05 GMT

I think you need to use getValue and setValue to work with field names as variables (not sure though).

Thanks, that was part of my problem. I wasnt using the getValue, and I also was trying to use the field describe object instead of the field name specifically.

for field in fieldlist:
fieldname = field.Name
cell value = row.GetValue(field)

Thats what worked for me. Thanks again for the help.

Re: Search Cursor - Search Entire Row?

BenYoungs — Wed, 07 Sep 2011 17:34:45 GMT

Leigh,

That is essentially what I ended up doing, except your code looks a little cleaner. Thanks for the help!