# Record and struct (GraphViz)

Record shapes give a node internal structure, and edges can point at an individual field. That is what makes Graphviz workable for data structure diagrams.

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## What this example shows

* shape=record with pipe-separated fields.
* Named ports, addressed as node:port in an edge.
* A linked list, drawn without any manual positioning.

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## A worked example

Open it, edit it, or copy the source below.

![Record and struct (GraphViz)](https://help.gocapable.com/images/att1423900783.svg)

The source, which you can paste into a new diagram and edit:

```
digraph structs {
  rankdir=LR;
  node [shape=record, fontname="Helvetica", fontsize=10];

  head [label="<f0> head", shape=plaintext];

  n1 [label="{<data> 42 | <next> next}"];
  n2 [label="{<data> 17 | <next> next}"];
  n3 [label="{<data> 93 | <next> null}"];

  table [label="{orders | {id | uuid} | {customer_id | uuid} | {status | text} | {total | numeric}}"];

  head:f0 -> n1:data;
  n1:next -> n2:data;
  n2:next -> n3:data;
  n3:next -> table [style=dashed, label="row per order"];
}
```

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## Making it your own

* Angle brackets define a port name; a colon in an edge addresses it.
* Braces flip the field direction, which is how you get a vertical record.
* Escape any literal pipe, brace or angle bracket inside a label.

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## Related

[Undirected graph (GraphViz)No arrows, because the relationship is symmetric.](https://help.gocapable.com/diagrams/undirected-graph-graphviz.html)

[State diagram (GraphViz)States as nodes, with a double circle for accepting.](https://help.gocapable.com/diagrams/state-diagram-graphviz.html)

[GraphViz examplesBack to the rest of these examples.](https://help.gocapable.com/diagrams/graphviz-examples.html)

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_Give it the edges. It does the rest._