Meaning
MySQL could not find the database named in the connection request.
Causes
- Database name misspelled
- Database not created yet
- Connecting to the wrong server
Fixes
- Verify the database name
- Create the database if it is missing
- Check you are connecting to the correct server
Example
ERROR 1049 (42000): Unknown database 'app_db'
FAQ
- Can this happen after a migration?
Yes, if the DB was not created in the target environment. - Is this a permissions issue?
No, it means the database name does not exist.
Contact
Contact your DBA to create the database or verify the server.