DBMigrationBestPractices

Database Migration Best Practices

Database migrations have historically been a source of considerable downtime when deploying new versions of Openstack services.

Schema Migrations

Schema migrations are any schema changes that create, drop or rename tables, columns, indexes and foreign keys. In some cases, making a schema change will cause the database engine to block reads and writes to the tables affected. Depending on the size of the table and the operation being performed, this can be up to an hour or more.

Data Migrations

Data changes are any migrations that alter data already in tables. For instance, moving data from one table to a newly created table would be a data migration.