for this migration is it necessary convert the database?

Thanks

Hello Franco, 

Here are the upgrade notes for OpenProject 7 to 8: https://www.openproject.org/docs/installation-and-operations/operation/upgrading/#upgrade-notes-for-openproject-7x-to-8x

You can find more information in our FAQ "Can I use MySQL instead of PostgreSQL?": https://www.openproject.org/docs/installation-and-operations/installation-faq/#can-i-use-mysql-instead-of-postgresql

Best regards
Samantha