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Once you establish full transaction processing by creating tables using the CREATE_MODE.TRNLOG_CREATE mode, you can take advantage of the automatic recovery feature. Atomicity will generally prevent problems of files being partially updated. However, there are still situations where a system crash can cause data to be lost. Once you have signaled the end of a transaction, there is still a "window of vulnerability" while the application is actually committing the transaction updates to disk. In addition, for speed considerations some systems buffer the data files and indexes so that updates may not be flushed to disk immediately. If the system crashes, and one of these problems exists, the recovery logic detects it. If you set up the system for automatic file recovery, the recovery logic automatically resets the table back to the last, most complete, state that it can. If any transaction sets have not been completed, or "committed", they will not affect the table.
