Rename (relational algebra)
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From Wikipedia, the free encyclopedia
In relational algebra, a rename is a unary operation written as where:
The result is identical to R except that the b attribute in all tuples is renamed to a.[1] For an example, consider the following invocation of ρ on an Employee relation and the result of that invocation:
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Formally, the semantics of the rename operator is defined as follows:
where is defined as the tuple t, with the b attribute renamed to a, so that:
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