data.home-assistant/docs/data_context.md

title	id	sidebar_label
Home Assistant Context	context	Context

Context is used to tie events and states together in Home Assistant. Whenever an automation or user interaction triggers a new change, a new context is assigned. This context will be attached to all events and states that happen as result of the change.

In the following example, all events and states will share the same context:

• Paulus arrives home, which updates device_tracker.paulus_pixel from not_home to home
• The automation "Paulus is home" is triggered and fires automation_triggered event.
• The automation calls service light.turn_on, which fires the service_call event.
• The light.turn_on service turns on the light which causes an update to the state of light.living_room.

A context object contains the following fields:

Field	Description
context_id	Unique identifier for the context.
user_id	Unique identifier of the user that started the change.
parent_id	Unique identifier of the parent context_id that started the change.

Context is not stored in their own table in the database. Instead, each event row maintains it's own columns to store context.

Example queries

Finding the context_id for a state in the database.

SELECT states.entity_id, states.state, events.context_id, events.context_user_id, events.context_parent_id FROM states LEFT JOIN events ON states.event_id = events.event_id

Finding the context_id for an event in the database.

SELECT events.event_type, events.event_data, events.context_id, events.context_user_id, events.context_parent_id FROM events