| Database
Management Systems |
| What
are backup and log? |
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| Ø | Backup is a copy of the |
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| entire database |
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| Ø | Log is a listing of activities |
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| that change database |
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| contents |
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| § | DBMS places three items |
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| in log: before image, |
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| actual change, and after |
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| image |
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