Search data where is null no longer works

General
1

I have a query that is comparing a related column to null. where columnName is null. This was working fine, but just recently stopped working. Why?

2

is “columnName” a relation column?

3

Yes it is.

4

Proper check for null in a relationship is done like this:

columnName.objecjId is null

Or

columnName.objectId is not null