Zero-downtime Database Migration tool

[tarakg]

We are exploring\evaluating tools provided by Oracle (or its partners) that ensures Zero-downtime Database Migration. Migration should include:

- Migration of data from one version of the application to another version with or without changes to the database schema.
- Migration of data from staging to production where staging was used for beta testing to host customers who created live data which need to be migrated to production. (SQL Server 2005 to SQL Server 2005, SQL Server 2005 to MySQL, etc)
- if a data type changes (say int to varchar) in staging database for a particular column in a table, the change migration should happen in the production database as well
- if a column is added\deleted in a table of staging database, the same table alteration should migrate to production database
- records in production database should not be deleted\truncated during data\schema migration
- maintain zero-downtime

By Zero-Downtime we mean: both the source and the target should be up and accept updates in real time during migration process. This should again be synced across and hence help to eliminate downtime during migration between various vendor databases.

We are not looking for any ETL product, but out-of-the-box products like GoldenGate and Celona that ensure Zero-downtime database migration.