Updating Sharepoint date field to null returning errors

[cwarshaw]

This is so strange. I have a long-running flow in Prod that has a simple expression to update a date field on a SP list and it works.

if(

    equals(items('Apply_to_each_-_Outcome')?['ArtifactStatus']?['Value'],'In Review'),

    utcNow(),

    ''

)

I do the same exact thing on another flow and it fails...

Error Text: The runtime value '""' to be converted doesn't have the expected format 'String/date'.

I don't know why it isn't like the null value in this context. I've looked at other threads and they suggest the same formula, I've tried passing in null variables, and all sorts off different things. As best I can tell it seems like it thinks it is undefined instead of null, but I have no idea why it would do that even when I hardcode in null.

[ManishSolanki]

Hi @cwarshaw 

Pls try the below expression:

if(

    equals(items('Apply_to_each_-_Outcome')?['ArtifactStatus']?['Value'],'In Review'),

    utcNow(),

    null

)

If this helps & solves your problem, please remember to give a 👍 and accept my solution as it will help others in the future.

Thanks

[cwarshaw]

Ya I've tried that as well. No luck... I've messed around with all sorts of permutations of null and ''. I've tried just leaving a variable blank and putting that in. All the same error.

[cwarshaw · Accepted solution]

So for anyone curious it was the difference between "Update Item" and "Update Item"... Now you might be saying to yourself "those are the same thing..." and you'd be right! But as you can see the code on the raw inputs is slightly different. "Method: Patch" vs "OperationID: Patch Item" if I copy and past my old action into my new flow it works. But anytime you try to create a new action it's going to use the new code which does not...

To me this seems like a pretty opaque bug that they should address. Especially because any new actions are affected. For now I'm going to use the workaround, but this was a waste of a day.

[CARTERA_1]

Do we have any update from Microsoft on a fix for this as it seems to be a glaring problem and is currently preventing one of our new flows being developed / published as we need to reset a date field to blank. Unfortunately we do not have another flow with the OLD patch method, so are limited by the NEW one

[JohnNovember]

Depending on which designer you're using, may not be an issue with your code:

https://www.youtube.com/watch?v=7I4b2vgG8y8 

[CARTERA_1]

Many thanks for your reply I think I fixed my issue, or it started working with the NULL value

[bcobra42]

This is still broken for me:

if(empty(outputs('Compose_Date')), if(empty(first(body('Get_items_Product')['value'])?['GroupDate']),null,first(body('Get_items_Product')['value'])?['GroupDate']), outputs('Compose_Date'))

null is returned as "" and errors the flow

[CARTERA_1]

Hi @bcobra42 - Mine seems to work with the NULL value see attached. In my flow I am using this twice as a filter condition, and to reset the date field.

Filter Condition

{
  "type": "If",
  "expression": {
    "and": [
      {
        "not": {
          "equals": [
            "@item()?['DateCompleted']",
            "@null"
          ]
        }
      }
    ]
  },

Update Item - partial view of code

      "item/DateCompleted": "@null",
      "item/IsActive": true,
      "item/NewImport": true

EDIT - The only other thing that I might have done was use the old Flow Designer and then saved rather than using the NEW designer.

[bcobra42]

I just set a text variable to @null and then replaced the null in my formula to the variable and it still gave the same error

[MauriceJutten]

I suggest viewing This  with the theme from Jaws, and be ready to hold onto your pants.

that actually did the trick for me ........ WTF. 

thnx @JohnNovember