Read isolation in Neo4j

Question

I know that the default isolation level is READ_COMMITTED and that reads are non-repeatable, but I'm not sure I understand everything this implies.

If thread A begins a transaction on an embedded database, then thread B begins a transaction and commits it, is it guaranteed or merely possible that subsequent reads within thread A's transaction will see the effects of thread B's transaction?

Answer 1

Yes, currently (due to read committed) you will see changes (commits) from another thread when you ask for them, e.g. by id or by index lookup.

This is planned to be changed in the future though with stronger isolation guarantees.

see: http://docs.neo4j.org/chunked/stable/transactions.html