DW Handbook
This page shows the name of the construct, its description
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Attribute
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Value
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Name
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Remove Duplicates
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Description
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None
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Function
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None
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Aim
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Allow a data engineer (user) to create a new relation containing no duplicate tuples
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Context
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None
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Rationale
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None
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Mechanisim
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None
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Formalisim
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δR = {(a1...an) | (a1...an) ϵ R ^ t1...tm ⊆ R } where R is a relation of n attributes (a) and m tuples (t) and tx!= ty for all 1 ≤ x,y ≤m and x!=y.
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Relational Algebra (RA)
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Similar to RA operation
Distinct (δ)
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Type
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Atomic
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Class
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None
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Transformation_category
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None
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Inputs
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| Inputs | Number of input datasets |
|---|
| None | None |
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Outputs
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| Outputs | Number of output datasets |
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| None | None |
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Used in stage(s)
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Cleaning
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