Persistence with Jakarta EE Persistence
摘要
Every application needs to store data during its execution in a durable data store. This store could be as simple as a flat file or as complex as a full-fledged database management system. The data store acts as the single source of truth for the application. For instance, your bank account balance is stored in some form of data store—this single data point is the only source of truth for the bank regarding how much money they're keeping for you.