neo4j - Cant use Merge inside foreach for existed nodes -

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i expecting following query create nodes (only if exits) , relations given source node (1) , list(2) way:

merge (p1:c9{userid: '1'}) p1, [{userid:"2"}] users  foreach (user in users | merge  ((p1)-[r1:follow]->(:c9 {userid: user.userid})))

thats outcome:

enter image description here

now if executing query again switching node id's way:

 merge (p1:c9{userid: '2'}) p1, [{userid:"1"}] users      foreach (user in users | merge      ((p1)-[r1:follow]->(:c9 {userid: user.userid})))

we got this:

enter image description here

neo4j duplicated me node id=1. want merge in case of existed nodes.

i expected see 2 nodes connected each other merging existed nodes.

any idea should fix?

thanks, ray.

i avoid foreach when can use unwind, start this:

merge (p1:c9 {userid: '1'}) p1, [{userid:"2"}] users  unwind users user merge (p1)-[r1:follow]->(:c9 {userid: user.userid})

sometimes want separate node creation relationship creation. if both @ same time, think neo4j can think want unique combination of node (with properties) , relationship.

merge (p1:c9 {userid: '1'}) p1, [{userid:"2"}] users  unwind users user merge (p2:c9 {userid: user.userid}) merge (p1)-[r1:follow]->(p2)

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