我想要查询下面例子中 m.name 不存在时 返回 n.name MATCH (n: people)-[r: in]->(m: room) WHERE EXISTS (m.name) RETURN n.name AS name

以下两种方法都是尝试, 但并没有查询到. MATCH (n:server_id)<-[:member]-(m:dens_id) WHERE EXISTS (n.name) AND NOT EXISTS (m.name) RETURN n.name

MATCH (n: people)-[r: in]->(m: room) WHERE NOT EXISTS (m.name) RETURN n.name AS name