Clear multi user fields in SharePoint Online using Power Automate with the REST API

I covered most types of fields previously but I didn’t cover the clear multi user field problem in SharePoint Online.

Clearing fields

A while back I wrote a post about clearing fields in Microsoft Flow. For details on how to update fields please look at the previous post.

Clear Multi user fields

I tried all sorts of ways but I kept hit all sorts of failures in my REST API call to SharePoint.

A collection of the errors that I saw:

An unexpected ‘StartObject’ node was found when reading from the JSON reader. A ‘PrimitiveValue’ node was expected.

A node of type ‘PrimitiveValue’ was read from the JSON reader when trying to read the contents of an entity set reference navigation link; however, a ‘StartObject’ or ‘StartArray’ node was expected.

A node of type ‘StartArray’ was read from the JSON reader when trying to read the contents of a resource reference navigation link; however, a ‘StartObject’ node or ‘PrimitiveValue’ node with null value was expected.

It was not until I looked at how to update a multi user field and then combined this with the how to reset a user field that I got to the solution. In my case I’ve got afield called CheckedBy.

The important bit in the above screenshot is the setting the Id to -1 and the StringId part of the field to an empty string.

'CheckedById': {
  '__metadata': {
    'type': 'Collection(Edm.Int32)'
  },
  'results': [
    -1
  ]
},
'CheckedByStringId': {
'__metadata': {
  'type': 'Collection(Edm.String)'
},
  'results': [
  '' ]
}

Ok, this is great, problem solved!

Pieter Veenstra

Is your business still running on paper trails, sprawling Excel files, or ageing Access databases? There's a better way — and I can show you exactly what it looks like. I'm the Technical Director of Vantage 365, a Microsoft solutions consultancy working with clients across the UK, the Netherlands, and worldwide. For over 30 years I've been turning messy, manual business processes into clean, automated systems that save time, reduce errors, and give teams the visibility they need to make better decisions. SharePains is not just any blog run by a Microsoft MVP. Have you ever used Try-Catch in Power Automate? The original post about Try-Catch in Power Automate can still be found on this site, https://sharepains.com/2018/02/07/try-catch-finally-in-power-automate-flow/ Or have you ever used the Pieter’s method to avoid variables and speed up your flows? https://sharepains.com/2020/03/11/pieters-method-for-advanced-in-flows/ You can contact me using contact@sharepains.com