UNIQUE Constraints for relationship for example Marriage (:Men)-[:MARRIED]-(:Women)
![shubham_jaizz00 shubham_jaizz00](https://community.neo4j.com/legacyfs/online/2X/6/6b77463ead9f109d009a2e76c64dbf670ddad449.png)
‎07-04-2019 12:36 AM
3 REPLIES 3
![stefan_armbrust stefan_armbrust](https://community.neo4j.com/legacyfs/online/1X/28c171c4f01d128874c25069bb7e7cbe8c98ceb8.jpeg)
‎07-04-2019 09:00 AM
Cardinality constraints are not yet implemented, you might see them in an upcoming release.
Meanwhile you can implement that behaviour yourself using a TransactionEventHandler
.
Reply
‎08-08-2019 10:06 AM
Hi Stefan -- Any news on implementing "Cardinality Constraints"? This would be very helpful for us to maintain the integrity of our schema. Will Neo4j 4.0 have this?
‎08-10-2019 01:59 AM
Unfortunately this won't be in 4.0, but it's rather high on the backlog.
![](/skins/images/35448E1D2B14DA61375C1E03B7139839/responsive_peak/images/icon_anonymous_message.png)