| File Generations | ||
| When a transaction file
is used to update a master file, the
process creates a new master file.
The old master file can then be deleted...no, wait!!...there may be problems just around the corner. In practice the old master file would be archived in case the update process has to be re-run.
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| Sometimes the old master file is referred to as the father
file and the new master file as the son
file.
When the update is next run... the son file becomes the father
file In practice companies will keep several generations of files. This is because there may be a problem (eg disk crash) and the update runs may have to be done again to re-create the current master file.
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| Exercise : | ||
| When a master file is updated, the new master
file created is known as the
file and the old master file is archived as the
file.
At each update ....the son becomes the father, the father becomes the grandfather etc.... Several of master files may be kept for disaster recovery purposes. |
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| (Green indicates success) | ||