Data migration from database and OJS file

Software Support
1

We have a trouble on the server we hosted OJS.
We need to build new site from scratch.
Is there the way to migrate the data from the old site using only database files and OJS files that are usually on parent directory of public_html.

What application are you using?
OJS 3.1.0

We want to build the new site OJS3.4.

— Hiroshi

2

We could upgrade to OJS3.3 from OJS3.1.

" How to Install and Upgrade" is very helpful.
We used dabase dump file, OJS_PUBLIC_PATH=“$OJS_WEB_PATH/public” and OJS_PRIVATE_PATH=“$OJS_ROOT_PATH/files”.

Thank you.