Hi All, I have checked the java doc of org.odmg.Database, it has a close() method and it suggest that "Databases must be opened before starting any transactions that use the database and closed after ending these transactions." That sounds reasonable but i have some troubles for my design. My general design is that each table has a corresponding class (call it entity class) whose properties are table columns. There is also a corresponding 'Manager' class whose methods are static methods and the purpose of them are to manipulate the entity class. My trouble is that should I open and close the Database object in each static method in the Manager class. If so, it looks ugly. If not, shall I maintain a singlton instance of the Database class for the whole application (I think it will have some performance issues). Any ideas? Thanks in advance. Regards, Boris
