Sometimes the project server shows that it cannot connect to the database, which may be due to the server's disk being mounted and suddenly not displaying, or other special issues such as not being able to load to the disk. As a result, the SQL Server on the disk becomes suspicious and the project cannot connect to the database.
Solution:
/*Change database to emergency mode */
Alter database database database name set emergency
/*Change to single user mode */
Alter database library name set single_User
/*Fix database logs */
Dbcc checkdb (database name, repair.allow_data_loss)
/*Restore multi-user mode */
Alter database library name set multi_User.
The above statements can be executed step by step to restore the normal state of the database. If there are jobs or other tasks in the database, it is best to pause first and then execute statements to restore the database to avoid causing additional losses.