Checks if a Cloud SQL for PostgreSQL instance is ready for a major version upgrade to the
specified target version.
The `target_database_version` MUST be provided in the request (e.g., `POSTGRES_15`).
This tool helps identify potential issues *before*
attempting the actual upgrade, reducing the risk of failure or downtime.
This tool is only supported for PostgreSQL primary instances and does not run on read replicas.
The precheck typically evaluates:
- Database schema compatibility with the target version.
- Cloud SQL limitations and unsupported features.
- Instance resource constraints (e.g., number of relations).
- Compatibility of current database settings and extensions.
- Overall instance health and readiness.
This tool returns a long-running operation. Use the `get_operation`
tool with the operation name returned by this call to poll its status.
IMPORTANT: Once the operation status is DONE, the detailed precheck results are
available within the `Operation` resource. You will need to inspect
the response from `get_operation`. The findings are located in the
`pre_check_major_version_upgrade_context.pre_check_response` field.
The findings are structured, indicating:
- INFO: General information.
- WARNING: Potential issues that don't block the upgrade but should be reviewed.
- ERROR: Critical issues that MUST be resolved before attempting the upgrade.
Each finding should include a message and any required actions. Addressing
any reported issues is crucial before proceeding with the major version upgrade.
If `pre_check_response` is empty or missing, it indicates that no issues were
identified during the precheck.
Running this precheck does not impact the instance's availability.