Database duplicate

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Database duplicate would be rows of a table that are repeated? Or would it be something more complex ?, this question fits into the context of database relationships

    
asked by anonymous 09.11.2016 / 13:24

1 answer

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Duplicate Definition:

  

Any object, written etc. representation or function identical to that of   another; copy, reproduction. - Google

I think you are referring to tuples, from your previous question, if you do not ignore this answer:

  

The body of a relationship in Database is a set; we know that in   math sets are not sorted (this means that the   elements are all different).

     

Note: A relation and a table are not the same, since a   table can contain duplicate rows, while a relation, for   definition, it never contains any tuples in duplicate. - Adapted by: Vítor Subhi

Bibliography and Suggestion: Date, C. J., 1941 - Introduction to Database Systems / C. J. Date; translation of Daniel Vieira. - Rio de Janeiro: Elsevier, 2003 - 8th Edition (Chapter 6)

    
09.11.2016 / 13:59
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