How to do Microsoft Graph API Filter on Lookup Column in SharePoint List Items?

Question

I am tried to apply Filter on Lookup column using Microsoft graph API filter. But it didn't filter. I have used below api to filter.

https://graph.microsoft.com/v1.0/sites/{sites}/lists/{listname}/items?expand=fields(select=Id,Title,LookUpcolumn)&$filter=Fields/LookUpcolumn eq 'value'.

Any help would be appreciated

Thanks in advance!

Answer 1

The the following expression demonstrates how to filter by lookup field id:

&filter=fields/<LookupFieldName>LookupId eq '<LookupFieldValue>'

Pay attention to lookup field name format, in Microsoft Graph lookup field value is exposed for Lookup Id by default

Example

Lets assume Employee list contains Department lookup field (refers to Department list), then the following query:

https://graph.microsoft.com/v1.0/sites/root/lists/Employee/items?expand=fields(select=Id,Title,Department)&filter=fields/DepartmentLookupId eq '<deplookupId>'

will return list items filtered by Department lookup Id value

Update

It seems Graph API does not support to apply filter by lookup value

As a workaround you could consider the following solution to filter by lookup value (requires two requests).

Given the above example

1)first step would be to query Departments list by Title and return Id property (which corresponds to DepartmentLookupId property in Employee list):

https://graph.microsoft.com/v1.0/sites/root/lists/Department/items?expand=fields(select=Id)&filter=fields/Title eq '<value>'

2) and then to query Employee list by Department lookup Id:

https://graph.microsoft.com/v1.0/sites/root/lists/Employee/items?expand=fields(select=Id,Title,Department)&filter=fields/DepartmentLookupId eq '<deplookupId>'