Zero-downtime Database Migration tool needed

[tarakg]

I am looking for a Zero-downtime Database Migration tool that would provide:

- 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)

- 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

- demonstrate zero-downtime

Please let me know if you are aware of a tool that provides such features.

[Shuja Ali]

I am not sure if you can achieve all this without a downtime. When a column is changed in the table it is bound to be locked for any data modifications, that in turn implies that there will be a downtime. And when you are moving from one server to another, don't you have to modify your applications to point to a new server? This itself means there will be downtime atleast in your applications till the migration is completed. You probably need to re-visit your approach.

Moving data from staging to production may not require a downtime, however, adding a column or changing the type would require sometime.

[tarakg]

I am basically concerned with the migration of data from staging to production without any downtime.

Just to add on to what I mentioned earlier about Zero-downtime data migration - Both the source and the destination can be up and accept updates in real time. This should again be synced across and hence help to eliminate downtime during migration between various vendor databases as well.

[dglienna]

Azure lets you have a production as well as staging, that can be switched to an alternate IP address and tested online, with totally different tables.

[tarakg]

What is "Azure"??