I encountered a problem: how to add attributes for 100,000 nodes, there are already 1000000 nodes in the database. The attributes to be added are stored in a csv table.Thank you very much!
Use LOAD CSV to import the data into Neo4j: https://neo4j.com/docs/cypher-manual/current/clauses/load-csv/
For each line in the CSV, match the node whose property you are adding, and then add it with Cypher according to the format of the CSV. This requires that you have a "key" to find the right node in your input CSV, but the rest is straightforward. You can use the cypher SET clause to put new attributes on any node you match.