Need to upgrade the Oracle database from 12C to 19C in different Servers using RMAN backup and restore method. DB Size is approx. 10TB and increasing on a daily basis. Below would be the steps:
- Install Fresh Oracle 19C in the unix server.
- Take RMAN Backup in 12C from the Current Unix Server and restore it to the 19C Server, which would take approx 12 Hrs.
- Now need to do some database changes in 19C which would take approx 5 Hrs.
- Make the 19C Server as main server. Now, to avoid this approx 17 Hrs of downtime. I am going to suggest below method:
Install and restore the Oracle 19C database and do the database changes on it one or two days before the go live date. At the time of go live, stop the application and take incremental backup from the live 12 Server and restore it to 19C Server. Will it be possible? Being new to the RMAN, my concern is, since database changes will be happening at both the databases, we only need to capture the changes happening on 12C and replicate them in 19C Server. While replicating these, we should not be reverting any changes done manually by us in the 19C database. Example : We added few tables and columns in 19C as part of database changes and inserted some records as well in the existing tables. But these changes are not present in 12C. Also in 12C, users are inserting records. Now at the time of final restoration, we should only be capturing the DML changes done only in the 12C and replicate them in 19C with keeping the 19C database changes, Is it possible to do so and if yes please explain the steps.
Currently, we are not taking the changes done in 12C Database and only considering 19C for the development purpose. While going live we need to incorporate the changes done in 12C along with keeping the changes done at 19C database.
