Walk the link graph

The engine reads your notes and their links as a labelled graph. Edges from link columns have the column’s name as their label, such as cast or genre; other resolved links have the label link, and each row has its table as its label.

The vault of the examples has three actors, two classic films, a viewing and two plain notes.

See what a note links to and what links to it

graph_neighbors returns a note’s links in both directions. Each link has a label: the link column it comes from (cast), or link for a link in the text.

graph_neighbors

{ "from_nodes": { "table": "actor", "where": { "name": "Cary Grant" } } }

Answer:

{
  "nodes": [
    {
      "path": "datanotes/main/public/actor/Cary Grant.md",
      "table": "main.public.actor",
      "counts": { "in:cast": 2, "in:link": 1 },
      "edges": [
        {
          "path": "datanotes/main/public/film/Charade.md",
          "table": "main.public.film",
          "label": "cast",
          "direction": "in"
        },
        {
          "path": "datanotes/main/public/film/His Girl Friday.md",
          "table": "main.public.film",
          "label": "cast",
          "direction": "in"
        },
        { "path": "Notes/Film night.md", "label": "link", "direction": "in" }
      ]
    }
  ]
}

Walk the links from a note

graph_traverse follows links breadth-first, in the direction you choose: out, in or both. Here it starts from Audrey Hepburn, goes up to two steps in both directions and keeps only films. It finds Charade, the film she’s in, and His Girl Friday, which the Charade note links to. via shows the route to each one.

graph_traverse

{
  "from_nodes": { "paths": ["datanotes/main/public/actor/Audrey Hepburn.md"] },
  "direction": "both",
  "tables": ["film"],
  "max_depth": 2
}

Answer:

{
  "start": ["datanotes/main/public/actor/Audrey Hepburn.md"],
  "nodes": [
    {
      "path": "datanotes/main/public/film/Charade.md",
      "table": "main.public.film",
      "depth": 1,
      "via": [
        {
          "from": "datanotes/main/public/actor/Audrey Hepburn.md",
          "label": "cast",
          "direction": "in",
          "to": "datanotes/main/public/film/Charade.md"
        }
      ]
    },
    {
      "path": "datanotes/main/public/film/His Girl Friday.md",
      "table": "main.public.film",
      "depth": 2,
      "via": [
        {
          "from": "datanotes/main/public/actor/Audrey Hepburn.md",
          "label": "cast",
          "direction": "in",
          "to": "datanotes/main/public/film/Charade.md"
        },
        {
          "from": "datanotes/main/public/film/Charade.md",
          "label": "link",
          "direction": "out",
          "to": "datanotes/main/public/film/His Girl Friday.md"
        }
      ]
    }
  ],
  "truncated": false
}

To read or total those rows, pass the paths to select_rows with where: {"path": {"in": [...]}}.

Find how two notes are connected

graph_path finds the shortest chain of links between two notes, or between two sets of notes.

graph_path

{
  "from_nodes": {
    "paths": ["Notes/Rewatch ideas.md", "datanotes/main/public/actor/Audrey Hepburn.md"]
  },
  "to_nodes": { "paths": ["Notes/Film night.md"] }
}

Answer:

{
  "found": true,
  "length": 2,
  "via": [
    {
      "from": "datanotes/main/public/actor/Audrey Hepburn.md",
      "label": "cast",
      "direction": "in",
      "to": "datanotes/main/public/film/Charade.md"
    },
    {
      "from": "datanotes/main/public/film/Charade.md",
      "label": "link",
      "direction": "in",
      "to": "Notes/Film night.md"
    }
  ],
  "from": "datanotes/main/public/actor/Audrey Hepburn.md",
  "to": "Notes/Film night.md"
}