Remove bidirectional relations in neo4j

Question

How to remove bidirectional relation between two nodes of same label and make it single relation between those two nodes irrespective of the direction.

For example:

(a:Label1)-[r]->(b:Label1) && (b:Label1)-[r]->(a:Label1)

What I need is either of a-[r]->b or b-[r]->a

If I use this:

 MATCH (a:Label1)-[r]->(b:Label1)

It is removing all relations.

Is it because of same label?

Answer 1

Use collect and tail function:

MATCH (a:Label1)-[r]-(b:Label1)
WITH a, b, collect(r) as rels
UNWIND tail(rels) as rel
DELETE rel