personClass.createProperty("name", OType.STRING).createIndex(OClass.INDEX_TYPE.UNIQUE);
personClass.createProperty("identifier", OType.STRING).createIndex(OClass.INDEX_TYPE.NOTUNIQUE);
db.getMetadata().getSchema().save();
// POPULATE TREE
db.begin();
PersonTree tree = new PersonTree();
tree.AddRoot("A", "B");
buildTree(tree, tree.root.getIdentity(), "A", subnodes, depth, 'A');
db.commit();