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is the existence of data that is additional to the actual data and permits correction of errors in stored or transmitted data. The additional data can simply be a complete copy of the actual data (a type of
60:(HDDs) into a logical storage unit that allows stored data to survive a complete failure of one drive. Data redundancy can also be used as a measure against
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database designs and results in the complication of database management, introducing the risk of corrupting the data, and increasing the required amount of
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For instance, when customer data are duplicated and attached with each product bought, then redundancy of data is a known source of
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since a given customer might appear with different values for one or more of their attributes. Data redundancy leads to
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checksumming in combination with copies of stored data to detect silent data corruption and repair its effects.
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219:"Operating Systems – Three Easy Pieces: Redundant Arrays of Inexpensive Disks (RAIDs)"
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is capable of detecting and correcting single-bit errors within each
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Remzi H. Arpaci-Dusseau; Andrea C. Arpaci-Dusseau (3 January 2015).
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prevents redundancy and makes the best possible usage of storage.
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that have values repeated unnecessarily in one or more records or
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Xin Li; Michael C. Huang; Kai Shen; Lingkun Chu (9 May 2010).
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Database systems: design, implementation, and management
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and generally should be avoided by design; applying
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44:For example, by including computed check bits,
41:of lost or damaged data up to a certain level.
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248:"How I Use the Advanced Capabilities of Btrfs"
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275:Database integrity: challenges and solutions
37:), or only select pieces of data that allow
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272:Jorge H. Doorn; Laura C. Rivero (2002).
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343:Introduction to Information Technology
278:. Idea Group Inc (IGI). pp. 4–5.
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39:detection of errors and reconstruction
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306:Peter Rob; Carlos Coronel (2009).
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88:While different in nature,
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374:Categories
359:4 February
325:22 January
291:23 January
257:26 January
231:16 January
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176:References
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395:Databases
139:See also
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