"For a selected file" multi-select choice inputs not being added to a multi-select choice column in Sharepoint using "Update file properties"

[GavinK]

A column "Business Unit(s)" in Sharepoint has a Checkbox list (select multiple) with options A, B, C, D (say).

I wish people to select multiple options (tick > Automate > Flow 1) to update this column so have set this up:

1. Trigger: For a selected file -- which includes an +Add an input "Business Units Input" (which is a multi-select list with options A, B, C ,D.
2. Action: Get file properties
3. Action: Update file properties -- which includes mapping of "Business Unit(s)" to "Business Units Input" (via "Enter custom value" option > Dynamic content...)
   1. Spoiler

      The Flow build forces me to add an "Apply to each" encompassing the "Update file properties" for some reason*. So then have to select "Current Value" via Dynamic Content

RESULT: The Flow only outputs one choice value to Business Unit(s).

4. * Weirdly, the drop down options displayed (above "Enter custom value") in "3" are from ANOTHER multi-choice list???!!! So I tried deleting the other multi-choice list in Sharepoint (it was redundant and completely different) but it then "2" picked up another choice list to display. So I deleted the "Business Units" in Sharepoint and recreated a new one "Business unit(s) with the same choices and then rebuilt 1-3 above. Same result. I have other single select choice lists and email inpputs in "3" that map OK.

I have other choice lists in "1" which were added to "3" in the same fashion as above except the "Apply to all" option was not added:

• Locations (multi-select from 4 choices)
  RESULT: [","] added to output (instead of distinctive choices)
• Doc Type (single select from 5 choices in "1" and 8 choices in "3").
  RESULT: Single choice outputted correctly
  
  

I also tried this (for the Business Unit(s) but it did not work (hence the Initialise variable step which is not used in this flow): Flow Update Multi-Select Column - @WonderLaura

[grantjenkins]

Hopefully this is what you're looking for.

For this example, I'm using the following list that has a Choice column called Business Unit(s) set to multiple select.

See full flow below. I'll go into each of the actions.

For a selected item has a multiple select setup to select the different businesses.

Select maps out each of the businesses selected as an object with a property called Value. This is the required format when updating multiple select Choice fields.

Update item uses the output of the Select to update the Businesses (in array mode).

If we selected an item and ran the flow, then selected our Businesses, the Business Unit(s) field would be updated with our new Businesses.