Before upgrading your production Liferay instance, you should do a trial run (even multiple runs) to make sure that you upgrade successfully and efficiently. Here’s the process:
Preparing a test server and database: This involves copying your current production installation to a test server and copying your production data backup to a test database. After you prune data from the test database (next step) you’ll test against it.
Pruning the database: Free your database of duplicate and unused objects. By removing them you can reduce upgrade time and improve your server’s performance.
Upgrading your test server and database: First you’ll optimize your database for the data upgrade. Taking time to do this can save upgrade time. Then you’ll do an upgrade test run (or several test runs) on a the pruned database copy. After going through the upgrade process, resolving any issues, and testing the upgraded server successfully, you can confidently upgrade your production database.
Now prepare your test environment.
Using a new separate server and database let’s you safely test upgrading.
Prepare a test server to use a copy of your production installation. Your test server must use the same Liferay version you’re using on production. Configure your server to use a new empty database for testing data upgrades.
Import data from your production database backup to the new empty database.
Next you’ll prune your database of unneeded data.