Does AWS neptune support multiple query/update statements being submitted to the HTTPS opencypher endpoint in a single request? I believe this is supported with Gremlin by simply separating each statement with a semi-colon. This is supported with the general cypher query against neo4j and other cypher supporting databases? If not, is there another way to submit multiple statements to be processed within a single transactional context when executing against the HTTPS opencypher endpoint?
I've tried submitting a single statement and that works correctly. I've tried submitting two statements separated by a semicolon and that does NOT work - I get an HTTP 400 / "MalformedQueryException" in the response.
Amazon Neptune today does not support multiple queries as part of a single transaction when using the HTTP endpoint and openCypher. It is supported, as you observed, for Gremlin queries.
One way to achieve this would be to use a supported Bolt client where you do have control over multiple queries within a single transaction.
This may change in the future, but for now, the HTTP openCypher endpoint does not support the same semi-colon delimited style of combining queries together that is supported for Gremlin queries.
Even though Gremlin does offer the support on Neptune, people typically use the Gremlin clients rather than the HTTP endpoint, which would be akin to using a Bolt client for the openCypher cases.