Mariadb Schema Management Deploy

MSM — Deploying a Schema Version

The final lifecycle step: apply a generated deployment script to a MariaDB server. One script both creates a fresh schema and upgrades any older released version to the target. Driven by msm.* + db.* tools of the mariadb-shell MCP server. See mariadb-schema-management for the model. Assume MariaDB 11.8.

Prerequisite

The deployment script for the target version must already exist (releases/deployment/<schema>_deployment_<version>.sql), i.e. the release was prepared, its update script filled, and the deployment script generated — see mariadb-schema-management-release. Check what is deployable with msm.get_deployment_script_versions.

Deploy

1. conn = db.connect(uri="root@host:port")        # open a connection first
2. msm.deploy_schema(
       connection_id=conn,
       version="1.1.0",        # optional; defaults to the latest generated script
       backup=True,            # optional; dump an existing schema before upgrading
       backup_directory="...", # optional; where the backup is written
   )

msm.deploy_schema runs the deployment script on that connection. It requires an open connection (that is why the tool is only available alongside the db.* group). With backup=True, an existing schema is dumped first so a failed upgrade can be restored.

Create-or-upgrade semantics

The deployment script decides what to do from the target schema's state:

• Empty / absent schema → created fresh at the target version.
• Existing MSM schema at an older released version → upgraded by running each msm_update_<from>_to_<to>() in sequence up to the target, then applying the idempotent objects and authorization.
• Already at the target version → nothing to change.

The msm_schema_version view is the source of truth for the installed version; it is set to 0,0,0 while a create/upgrade is in progress. The script aborts with a clear SIGNAL error when it cannot safely proceed:

• a non-MSM schema of the same name exists (no msm_schema_version view);
• the schema is stuck at 0,0,0 (a previous run was interrupted);
• the current version has no update path in this deployment script.

Inspect state with msm.get_last_deployment_version (what a server would report) and msm.get_last_released_version / msm.get_released_versions (project side).

Guidelines

• Deploy the generated script only; never a hand-edited deployment file.
• Use backup=True for production upgrades so a failure is recoverable.
• Upgrades are only possible along the released-version chain — if a server is on a version with no update script leading toward the target, the deployment will refuse it. Ensure every release was prepared with its update script filled.
• Re-running the same version is safe (idempotent objects re-create cleanly; the create/upgrade dispatcher is version-guarded).

See Also

• mariadb-schema-management — lifecycle overview and full section model.
• mariadb-schema-management-release — generating the deployment script this step runs.
• mariadb-schema-management-develop — the development script releases are cut from.