Tietokantamigraatio

Tietokantamigraatio, or database migration, refers to the process of moving data from one database system to another, or from one database structure to a new one. This can involve changes in the database management system (DBMS), the data model, or even the storage format. Common reasons for undertaking a database migration include upgrading to a newer version of a DBMS, switching to a different type of database (e.g., from relational to NoSQL), consolidating multiple databases, or moving to a cloud-based solution.

The process typically involves several stages. First, a thorough analysis of the source and target databases is performed to understand the schema, data types, relationships, and any stored procedures or triggers. Next, a migration strategy is chosen, which might involve a direct transfer, an incremental approach, or a complete rebuild. Data extraction from the source system is then carried out, followed by transformation to match the target schema and data types. Finally, the transformed data is loaded into the target database.

Data integrity and consistency are paramount during a migration. This often necessitates downtime for the source system to prevent data changes during the migration process, although techniques for minimizing downtime, such as blue-green deployments or logical replication, are increasingly employed. Thorough testing is crucial at various stages to ensure that all data has been migrated accurately and that applications can function correctly with the new database. Rollback plans are also essential in case of unexpected issues.