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I am not a very good programmer and do not claim to be an expert in arc. I am going to try to explain this problem as clearly as possible and any solutions that you guys may have would be helpful.

I am pulling multiple data sources from varying schemas and need to run a field calculation on two of the fields. Here is my problem, the two fields dont always exist. So some features have a "Field 1" and "Field 2", some only have a "Field 1" and some only have a "Field 2". When I try to run an iterated create field to create "Field 1" it will flat line as soon as it hits the first feature class with "Field 1" already existing. Is there a way to tell the model to continue running even if it hits a failure on a single iteration pass? Or is there another workaround that has alluded me?

I have also tried to do an iterated select on these features as well but like above as soon as it hits a feature that does not have the field i am searching for, it fails.

Any help would be greatly appreciated. I am working in arc10. Thanks!

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Looking quickly at this I would expect that you would need to use ListFields in a Python script tool to incorporate the necessary logic. – PolyGeo May 27 '13 at 9:05

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