Query examples using CSV - Neptune Analytics

Query examples using CSV

In this example, the query returns the number of rows in a given CSV file: 

CALL neptune.read(
  {
    source: "<s3 path>",
    format: "csv"
  }
)
YIELD row
RETURN count(row)

You can run the query using the execute-query operation in the AWS CLI: 

aws neptune-graph execute-query \
  --graph-identifier ${graphIdentifier} \
  --query-string 'CALL neptune.read({source: "<s3 path>", 
    format: "csv"}) YIELD row RETURN count(row)' \
  --language open_cypher \
  /tmp/out.txt

A query can be flexible in what it does with rows read from a Parquet file. For instance, the following query creates a node with a field set to data from a CSV file: 

CALL neptune.read(
  {
    source: "<s3 path>",
    format: "csv"
  }
)
YIELD row
CREATE (n {someField: row.someCol}) 
RETURN n
Warning

It is not considered good practice use a large results-producing clause like MATCH(n) prior to a CALL clause. This would lead to a long-running query due to cross product between incoming solutions from prior clauses and the rows read by neptune.read. It is recommended to start the query with CALL neptune.read.