# Get graph edge

Source: https://stratadb.org/docs/reference/graph/edge/get

Reads one edge by its `(src, edge_type, dst)` triple, returning its weight, properties, and last-write commit coordinates. A missing edge reads back as no data. Accepts `as_of` for time travel.

Optional reads distinguish present data from missing data. When version or timestamp facts exist on the executor output, SDK mappings should preserve them.

## Examples

Read an edge, or nothing if absent.

### CLI

```console
$ strata graph create social
$ strata graph add-node social alice
$ strata graph add-node social bob
$ strata graph add-edge social alice knows bob
$ strata graph get-edge social alice knows bob
$ strata graph get-edge social alice knows absent
```

### Wire

```json
{"graph":"social","type":"graph_create"}
{"graph":"social","node_id":"alice","type":"graph_add_node"}
{"graph":"social","node_id":"bob","type":"graph_add_node"}
{"dst":"bob","edge_type":"knows","graph":"social","src":"alice","type":"graph_add_edge"}
{"dst":"bob","edge_type":"knows","graph":"social","src":"alice","type":"graph_get_edge"}
{"dst":"absent","edge_type":"knows","graph":"social","src":"alice","type":"graph_get_edge"}
```

## Parameters

| Name | Type | Required | Description |
|---|---|---|---|
| `as_of` | `integer` | no | Optional timestamp in microseconds. Reads the graph state visible at that instant. |
| `dst` | `string` | yes | Destination node id. |
| `edge_type` | `string` | yes | Edge type. |
| `graph` | `string` | yes | Graph name. |
| `src` | `string` | yes | Source node id. |

Plus the optional scope: `branch` and `space` (default to the session branch and the `"default"` space).

## Returns

`Maybe<GraphEdgeDataOutput>` — a miss returns nothing rather than raising.

## Errors

- [`failed_precondition.engine.runtime_closed`](https://stratadb.org/e/failed_precondition.engine.runtime_closed)
- [`not_found.engine.branch`](https://stratadb.org/e/not_found.engine.branch)
- [`invalid_argument.engine.product_space`](https://stratadb.org/e/invalid_argument.engine.product_space)
- [`invalid_argument.engine.graph_name`](https://stratadb.org/e/invalid_argument.engine.graph_name)
- [`not_found.engine.graph`](https://stratadb.org/e/not_found.engine.graph)
- [`invalid_argument.engine.graph_node_id`](https://stratadb.org/e/invalid_argument.engine.graph_node_id)
- [`invalid_argument.engine.graph_edge_type`](https://stratadb.org/e/invalid_argument.engine.graph_edge_type)

## Invocation

- CLI: `strata graph get-edge`
- Wire type: `graph_get_edge`