Powerapps lookup person or group field from sharepoint liste

[Lifcitz1912]

Hello 

In power apps, I would like to show in the lookup field (in form based in SharePoint Liste A) the value which is based in another column in SharePoint liste B

it's work with static input using this fonction : LookUp(Collab; column4.Value="Mehdi").SUP

but when i did the same fonction basing on person or Group Filed :  LookUp(Collab; DEMANDEUR=).SUP they told me that this formula does not work correctly on large datasets

Did i miss something ?? you can see below a screenshot

[rebeccas]

Here is what I use for getting supervisor on my end.

Apps OnStart:
Set(gvCurrentuser, Office365Users.MyProfileV2());
Set(gvCurrentManager, Office365Users.ManagerV2(gvCurrentuser.userPrincipalName))

Combo Box (Supervisor) Default Selected Items:

{DisplayName: gvCurrentManager.displayName, Claims: "i:0#.f|membership|" & gvCurrentManager.userPrincipalName}

[Lifcitz1912]

Thank you rebecaas for your response,

Actually the problem is to identify the supervisor,Head of Department, HR, Director ... and all of them, they are already stored in sharepoint liste that why if I find a way to resolde the function LookUp(Collab; DEMANDEUR=).SUP so  I can after get the supervisor, Head of Department HR Director based on this sharepoint list