Indexing links

I have a graph with a lot of relationships and I would like to have an index on one link type.
The goal is to run queries such as

where l.uuid = "405b6b8b-139a-4569-a695-708d018e61c1"
return n, p

And avoid the huge AllNodesScan, expandAll and filter of this query. What I need is simply a constraint assert unique on link property.
Is that possible ? I tried the relationship property existence constraint but it doesn't index things.

In 3.5 you can have fulltext indexes on relationships, see

Excellent, works perfectly as expected, thank you very much :slight_smile: