> ## Documentation Index
> Fetch the complete documentation index at: https://docs.metriport.com/llms.txt
> Use this file to discover all available pages before exploring further.

# composition_event

The clinical service, such as a colonoscopy or an appendectomy, being documented (`Composition.event[]`).

**Primary Keys:**

* composition\_event\_id

**Foreign Keys:**

* composition\_id - links to the [composition](/medical-api/handling-data/schema-v100/composition/base) table

| Column                 | Data Type | Description                         |
| ---------------------- | --------- | ----------------------------------- |
| composition\_event\_id | varchar   | Unique identifier for the event row |
| composition\_id        | varchar   | Parent composition                  |
| period\_start          | datetime  | Start of the event period           |
| period\_end            | datetime  | End of the event period             |

**Related Tables:**

**Parent:**

* [composition](/medical-api/handling-data/schema-v100/composition/base)