topic Re: Data is Null Error in ArcGIS Survey123 Questions

Data is Null Error

BrandonA_CDPH — Wed, 02 Mar 2022 21:04:02 GMT

I have generated a Survey123 form using Survey123 Connect. I can't just "eliminate and add back in (which is my usual method of troubleshooting)" because I can't get the error to show on my side. Two users are both trying to test it and get the following error: "Data is Null. This method or property cannot be called on Null values."

I am using Connect version 3.13.239 and all three of us are using version 3.13 of the Field App. This has happened on desktop and iPhones for both users. I, as the survey owner, have had no problems at all on iPhone, iPad or computer.

I can't find any documentation showing what this error means or how to chase it down. Any hints are appreciated.

I can anonymize the form if needed and post, but right now it has some internal references that make it harder to share publicly.

Thanks in advance.

Re: Data is Null Error

abureaux — Wed, 02 Mar 2022 21:13:29 GMT

Without more info, it's hard to say (at least for me!). You may wish to include the XLSX form to help with troubleshooting.

On the off chance it is something simple, have you tried submitting a survey with minimal data? Basically, enter data in only the fields marked required and leave all others empty (this also includes removing any "default" text that may exist). Then submit the survey and attempt to do with that survey whatever it is you normally do. If you get the error, it likely means you have at least one field that needs to be made required to stop users from submitting NULL data in it.

Re: Data is Null Error

BrandonA_CDPH — Wed, 02 Mar 2022 22:37:41 GMT

Thank you for the suggestions. I have been racking my brain all day on this

I have a lot of required questions, so I can try making less required, but I don't know if that will help. It's kind of a long form, but I have attached what I'm working with. I'm trying to figure out what the vague error message is telling me. It has something to do with null data, but I haven't had a problem with blank fields in the past.

There's a likelihood that I have just spent too much time with this thing and I'm missing something basic. 🙂

Thanks.

Re: Data is Null Error

abureaux — Wed, 02 Mar 2022 22:45:09 GMT

Sorry. To clarify, I don't mean make fewer required questions. I mean just enter data for ONLY the required questions. I've had surveys where some field that I didn't think needed to be required ended up causing me issues if they were left blank. So, submitting and working with a survey that has the minimal amount of data can sometimes help root out strange behaviour.

I will have a look at the XLSX and see if it works for me.

Re: Data is Null Error

abureaux — Wed, 02 Mar 2022 22:49:28 GMT

I will still look at this as-is, but I wanted to mention quickly that some of your issue may be related your names. Everything in the name column needs to be lowercase (e.g., OverallNote vs overallnote). I will run through the document and make this change, but wanted to mention this as we will technically be working with different documents after that change is made.

Re: Data is Null Error

BrandonA_CDPH — Wed, 02 Mar 2022 23:07:19 GMT

Thanks. I can make that change in the final version and will keep that in mind.

Re: Data is Null Error

BrandonA_CDPH — Wed, 02 Mar 2022 23:08:26 GMT

That's a good tip. I'll go through and double check things. I do have some hidden and calculated fields, so maybe it's something with those.

Re: Data is Null Error

abureaux — Wed, 02 Mar 2022 23:29:12 GMT

I had to make three changes to get this to work:

All names are now lowercase (publishing requirement);
The choice list corract was missing (I would guess because it contained sensitive info and you removed it?). I replaced this with a placeholder for my test; and
I had to remove the field actaddress (and the few associated fields) because it was a geolocator which I could not replicate.

I published from Connect 3.14.256 and filled out in Field App 3.14.237. I was able to successfully send the survey using the method I described above (I.e., only filling in required fields) without any issue.

At what point were your users experiencing this issue? I am wondering if I am missing a step. But right now, I am unable to reproduce the issue.

Before you go too far with your own testing, I would suggest making all of the field names lowercase and having users test again just in case that was causing some odd behaviour.

Re: Data is Null Error

BrandonA_CDPH — Wed, 02 Mar 2022 23:42:20 GMT

Thank you for the thorough examination. It sounds like you had the same experience I did (no issues). The users are able to fill in all the fields, but when they submit, it throws the error. I'll try making my field names lowercase and have them try again. Hasn't been an issue in the past, but worth a shot.

Re: Data is Null Error

joe — Thu, 03 Mar 2022 04:24:58 GMT

This reminds me of a similar issue I had... Strange things could happen when geometry isn't right.

I noticed in your XLSX there are calculations of geopoint and geoshape. Try to alter the calculation to avoid null values, e.g. for "ActLoc":

'' + concat(number(${ActY_null}),' ', number(${ActX_null}))

Or use an interim question for the above calculation.

Hope it helps 🙂

Re: Data is Null Error

BrandonA_CDPH — Thu, 03 Mar 2022 16:19:55 GMT

Thanks @joe . I’ll take a look at the geometry specifically. Trying to make things easier on the users and may have gotten the computer part all confused.

Re: Data is Null Error

BrandonA_CDPH — Thu, 03 Mar 2022 18:06:54 GMT

Thank you all for the assistance. To conclude, this is what happened.

I had a repeat with a geopoint question. The lat and long from those points were joined together to give the geoshape for the main entry. Problem was, if the user only entered 1 or 2 points, there was not an area and the geometry was invalid (null) for the main entry. This threw the error.

I didn't get this error because I knew it needed an area and used the map in the geoshape question to override the geometry to an area.

Long story short, if you have geopoints joining to create a geoshape, require three or more points or have another method to stop the invalid geometry.

Took me a while, but I got it! Thank you @joe and @abureaux for taking the time to comb my long xls file and help me see the light on this one.