I try to explain. I have a graph where each node can have only one connection to the other. If I check the presence of n links between two nodes then delete n-1 connections. -- View this message in context: http://drools.46999.n3.nabble.com/Help-write-rule-drools-tp4029841p4029869.html Sent from the Drools: User forum mailing list archive at Nabble.com.