如何使用节点 ID 在两个现有节点之间创建关系？

Question

I am trying to create a relationship between two existing nodes. I am reading the node ID's from a CSV and creating the relationship with the following query:

LOAD CSV WITH HEADERS FROM "file:///8245.csv" AS f
MATCH (Ev:Event) where id(Ev) =f.first 
MATCH (Ev_sec:Event) where id(Ev_sec) = f.second
WITH Ev, Ev_sec
MERGE  (Ev) - [:DF_mat] - > (Ev_sec)

However, it is not changing anything the database. How can I solve this problem?

Thanks!

Answer 1

I solved the problem. So, I again queried for the ID(node) and this time I exported them as a string (by using toString(ID(node)) ). Then while loading to the database, I converted them to Integer. The query is as follows:

LOAD CSV WITH HEADERS FROM "file:///8245_new.csv" AS csvLine
match (ev:Event) where id(ev)=toInteger(csvLine.first)
match (ev_sec:Event) where id(ev_sec)=toInteger(csvLine.second)
merge (ev)-[:DF_mat]-> (ev_sec)