How does JE Concurrent Data Store (CDS) differ from JE Transactional Data Store (TDS)?
Berkeley DB, Java Edition comes in two flavors, Concurrent Data Store (CDS) and Transactional Data Store (TDS). The difference between the two products lies in whether you use transactions or not. Literally speaking, you are using TDS if you call the public API method, EnvironmentConfig.setTransactional(true). Both products support multiple concurrent reader and writer threads, and both create durable, recoverable databases. We’re using “durability” in the database sense, which means that the data is persisted to disk and will reappear if the application comes back up after a crash. What transactions provide is the ability to group multiple operations into a single, atomic element, the ability to undo operations, and control over the granularity of durability. For example, suppose your application has a two databases, Person and Company. To insert new data, your application issues two operations, one to insert into Person, and another to insert into Company. You need transactions if yo
