neo4j - Checking NULLS in an OPTIONAL MATCH -


i have cypher query this:

match (start:startlabel) optional match (start)-[:a]->(end1:endlabel) optional match (start)-[:b|c]->(middle:middlelabel)-[:d]->(end2:endlabel) not(end1 null , end2 null) return *

in graph model there multiple valid ways reach (end) (start) want make sure result matches @ least 1 of possible optional match paths. reason continue results both end1 , end2 null where clause. missing how cypher processes optional match , where together?

here alternate way results:

match (start:startlabel)-[:a]->(end:endlabel) return start, null middle, end union match (start:startlabel)-[:b|c]->(middle:middlelabel)-[:d]->(end:endlabel) return start, middle, end

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