When I run the following neo4j query, the update summary says "Set 1 property" the first time, but if I re-run it the summary says "(no changes, no records)":
match (u:users {id: $id) set u.isOnline = null
On the other hand, when I run the following query (with the same $token) multiple times the summary always says "Set 1 property":
match (u:users {id:$id}) set u.token = $token
Why is the behavior different?
yes, that's what neo4j behaviour so you must aware of this when working with null values
When updating null neo4j pre check if value exists like node exists, but it not gonna check for string or an other type of values like array
so you always get true for string update even for same value