The DB->close() database handle closes the DB handle. By
default, DB->close() also flushes all modified records from the
database cache to disk.
There is one flag that you can set to customize DB->close():
-
DB_NOSYNC
- Do not flush cached information to disk.
It is important to understand that flushing cached information
to disk only minimizes the window of opportunity for corrupted data, it
does not eliminate the possibility.
While unlikely, it is possible for database corruption to happen if a
system or application crash occurs while writing data to the database. To
ensure that database corruption never occurs, applications must either:
- Use transactions and logging with automatic recovery.
- Use logging and application-specific recovery.
- Edit a copy of the database, and, once all applications
using the database have successfully called DB->close(), use
system operations (for example, the POSIX rename system call) to
atomically replace the original database with the updated copy.