Without the information AHA requested there isn’t much advice we can give you. I am going to assume you were using mysql or mariadb in which case the first thing I would do is to make a mysqldump of everything.
sudo mysqldump --all-databases > alldb.sql
next I would cat the file to be sure there was information in it.
then I would place that in a gz file.
tar -cf alldb.sql.tar.gz alldb.sql
Here is some documentation on mysqldump
After that I would uninstall and purge the config files for your db.
sudo apt purge mysql
sudo apt purge mariadb-server
Then I would remove all associated packages…
sudo apt autoremove
Then I would clean all files…
sudo apt clean
After that I would install your db of choice but if you feel the old database was corrupted or compromised you should get a controlled environment where you can install your database of choice and disconnect from the web to prevent sending any information. Install the db and import the database. sift through the tables. Find what you cant that is safe and dump it to files then import into your new database on the main server.
Also to secure mysql you should run the following command.
All of this and more is discussed here…
Hope this helps!
MySQL and MariaDB are relational databases used in many unique situations. However, they can pose a security risk for your system and your data if you do not secure them properly. This guide will introduce some basic considerations and steps you can take to ensure that your data is more secure.