Symptoms
The checkbox next to the database name is qrayed out and the database name contains (This resource is used by the installed site application).Cause
The database is used by an installed site application. It can be removed only along with the respective site application.Resolution
To remove the database the parent application needs to be removed from Plesk as well: Plesk, Domains, domain.tld, Application Vault / ASP.NET Web Applications.If no applications that may be using the database are displayed, the database needs to be marked as non-belonging to any application, using the provided steps below. This problem could have happened during errors when deleting an site application.
1. Find the database ID in the Plesk database:
set @db_id = (select id from data_bases where name=’db_name’);2. Delete the connection between application and the database.
set @app_id = (select app_id from siteappresources where type='database' and res_id=@db_id);
delete from siteappresources where app_id=@app_id;3. Remove the database using Plesk, domains, domain.tld, Databases.