I am currently running some tests with a large JSON data string. I suspect that there might be a character limit where you can add input parameters but I am not sure. Is there a character limit for a string in ArcMap? This is json data I pulled from a GeoProcesssing Server. Here is what I am talking about:


  • It's saying the limit is 29999, this must be a lib limit as a python string can be very long, see stackoverflow.com/questions/1739913/…. In the lib that the python calls the input must be (in C) char* InputLabelName = new char[299999]; which would be limiting the string... I have encountered this before and it was not python that was limiting the string. – Michael Stimson Sep 13 '18 at 23:24
  • This may or may not be related to gis.stackexchange.com/questions/19721/… – PolyGeo Sep 14 '18 at 1:20
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    There's no practical limit on python strings. ArcGIS is limiting the tool inputs to 30K characters. Your JSON parsing is failing because it's getting a truncated string. Workaround, write json string to temp file, pass that to the tool and load that. – user2856 Sep 14 '18 at 1:33
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    Possible duplicate gis.stackexchange.com/q/130349/2856 – user2856 Sep 14 '18 at 2:31
  • @Luke Thanks for the suggestion, but this string will change. I looked at the link that both PolyGeo and you sent. They answer part of my question but how would I run my script from command line or somewhere else? – Demon Sep 14 '18 at 16:25

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