For users with a large database and shell access, it is much quicker to update the database from the command line.
I recommend modifying Knowledge Base Updating 3.2.x
9. Follow the steps to update the database and let that run to completion.
9. Follow the steps to update the database and let that run to completion.*
*If you have shell access to your server, you may wish to update via the command line interface. From your board's root, execute the following command: php bin/phpbbcli.php --safe-mode db:migrate.