See how we add CREATE support here: https://github.com/jakewins/gqlite/pull/4/files#diff-e6ecf87708389c5c6e42b32a67b1b2c1R516

You check if an identifier is "bound", so you tell that this query is invalid (because n doesn't point to anything): SET n.name = "bob", but this one is ok: MATCH (n:Person) SET n.name="Bob", see the description here