# Warnings and Considerations
**When querying journey history across versions:**
`
step_id
` is not stable across journey versions. All step_id’s will change between versions.`
step_name
` is always unique within a journey version (whether it changes or not between versions depends on whether the user modifies it).
**Joining journey history data to other data sources**:
`operation_id
` is available in personalization (using `simon.operation_id
` in Jinja). This makes it useful to join to other data sources, such as engagement events.
# Journey history events by email
# Query for metadata
# All history for a specific Journey