Why should I understand Database Transaction Logs / Redo- and Archive log files ?
Although the management of Transaction Log Files / Redo- and Archivelog Files is the System DBA’s job, • you should know: Each insert / update / delete not only changes the database the data block containing the data, but additionally creates a “journal”-information about this change in a separate file. Those files are called “Transaction Logfiles” or “Redo- / Archivelog Files” and are used to “roll forward” after a crash or restore. This feature allows that you can recover the last committed transaction even after restoring your backup from last nigh! • You need to be aware that unusual high insert / update / delete activity will create unusual high amount of Transaction Log or Archivelog Files which can cause that filesystem to run full and freeze your database! We highly recommend to read our free white paper Transaction Log Volume / Archive Log Volume! • Therefore you need to test on a full-sized test database (“Pre-Production Environment”) this unusual job and ask your DBA to meas
