Solutionunvalidated

Preserve properties explicitly. — Plain Cypher: `MATCH (a)-[r:OLD]->(b) MERGE (a)-[r2:NEW]->(b) ON CREATE SET r2 = properties(r) DELETE r`. Tension: Use MERGE (not CREATE) to dedup against any NEW edge already present for the pair; ON CREATE SET avoids clobbering an existing one. Outcome: Both forms are idempotent (a re-run matches no OLD edges).

35a8e14f-26fa-4603-838c-5c194729057c

Preserve properties explicitly. — Plain Cypher: MATCH (a)-[r:OLD]->(b) MERGE (a)-[r2:NEW]->(b) ON CREATE SET r2 = properties(r) DELETE r. Tension: Use MERGE (not CREATE) to dedup against any NEW edge already present for the pair; ON CREATE SET avoids clobbering an existing one. Outcome: Both forms are idempotent (a re-run matches no OLD edges).