You need to do the DB migration which is mandatory for every upgrade of the product. It is a simple command to launch (the whole migration process is written in the Installation guide).
The SVN migration is automatic when connecting to the project with your newest version of the studio. So you don't have to do anything with your SVN repository.

Hello

I wonder how the case of service pack, e.g. 3.2.2 to 3.2.3.
Are DB metadata and SVN metadata migration required in addition to redeploy TAC?

In fact, 3.2.2 and 3.2.3 are the same version and 3.2.3 have some fixed bug. So, you can use the same DB metadata and SVN medata when you migrate project from 3.2.2 to 3.2.3. To do:
1)Put Talend Adminsitration Center 3.2.3 to webapp folder of apache.
2)Go to db config page and use the same db metadata as 3.2.2.
Best regards

          shong

Hello

Can we just redeploy the new version/instance of webapp? Can we still use our MySQL based Admin metadata information and Project metadata, same database, JDBC connection string etc.?

You need redeploy Talend Adminsitration Center 3.2.3 and create a new mysql db for 3.2.3, about the project items, export all the project items from old version, and then import them into the new project.

Best regards

          shong