Path Traversals
Path traversals map traversal steps to a location to use in the event that a previous location must be revisited.
This path traversal starts at an ingredient, traverses to a recipe, and eventually finds a book that contains the recipe with the ingredients specified.
g.V().hasLabel('ingredient').has('name',within('beef','carrots')).
in().as('Recipe').
out().hasLabel('book').as('Book').
select('Book','Recipe').
by('name').
by('name').
path()The output for this traversal lists each result:
==>path[v[dseg:/ingredient/3028], v[dseg:/recipe/2007], v[dseg:/book/1004],
{Book=The Art of Simple Food: Notes, Lessons, and Recipes from a Delicious Revolution, Recipe=Carrot Soup}]
==>path[v[dseg:/ingredient/3001], v[dseg:/recipe/2001], v[dseg:/book/1001],
{Book=The Art of French Cooking, Vol. 1, Recipe=Beef Bourguignon}]Another path traversal creates a tree that emanates from a vertex label, in this case a book.
g.V().hasLabel('book').in().tree().by('name').next()The output for this traversal lists each result:
==>Simca's Cuisine: 100 Classic French Recipes for Every Occasion={Simone BECK={}, Patricia SIMON={}}
==>The Art of French Cooking, Vol. 1={Julia CHILD={}, Beef Bourguignon={}, Salade Nicoise={}, Simone BECK={}}
==>The Art of Simple Food: Notes, Lessons, and Recipes from a Delicious Revolution={Kelsie KERR={}, Alice WATERS={}, Carrot Soup={}, Patricia CURTAN={}, Fritz STREIFF={}}
==>The French Chef Cookbook={Julia CHILD={}}Each book lists the authors and recipes that are included in the book.
Another tree traversal discovers all the vertices that are on outgoing tree branch from a recipe that attach with an includes edge.
g.V().hasLabel('recipe').out('includes').tree().next()The output for this traversal lists each result:
==>Roast Pork Loin={red wine={}, pork loin={}, chicken broth={}}
==>Spicy Meatloaf={bacon={}, celery={}, pork sausage={}, onion={}, ground beef={}, green bell pepper={}}
==>Beef Bourguignon={mashed garlic={}, butter={}, onion={}, tomato paste={}, beef={}}
==>Carrot Soup={butter={}, onion={}, chicken broth={}, carrots={}, thyme={}}
==>Rataouille={mashed garlic={}, yellow onion={}, olive oil={}, zucchini={}, eggplant={}}
==>Salade Nicoise={tuna={}, hard-boiled egg={}, olive oil={}, tomato={}, green beans={}}
==>Wild Mushroom Stroganoff={mushrooms={}, yellow onion={}, egg noodles={}}
==>Oysters Rockefeller={oyster={}, chervil={}, parsley={}, celery={}, fennel={}, shallots={}, Pernod={}}Each recipe lists the ingredients required to make the recipe.
