Total quota size is the disk space allocated for the database file and the transaction log file. Database/Transaction Log file quota ratio is the portion of disk space allocated for the database file. If you set the total quota size to 100 MB and the database/transaction log file quota ratio to 40%, then the maximum database file quota is 40 MB and the maximum log file quota is 60 MB. The more dynamic your database is, the bigger transaction log file quota ratio should be.
To change the quota: