# 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