Which property ensures that information decomposed across many relations can be reconstructed using natural joins?a.Lossless-join propertyb.Atomicity Propertyc.Consistency Propertyd.Dependency preservation property
Question
Which property ensures that information decomposed across many relations can be reconstructed using natural joins?a.Lossless-join propertyb.Atomicity Propertyc.Consistency Propertyd.Dependency preservation property
Solution
The property that ensures that information decomposed across many relations can be reconstructed using natural joins is the Lossless-join property.
Here's a step-by-step explanation:
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In the context of database normalization, decomposition is the process of breaking down a table into two or more tables. The goal is to eliminate redundancy and dependency.
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The Lossless-join property is one of the fundamental properties that a good decomposition should have. It ensures that when the tables resulting from the decomposition are joined back together (reconstructed), all the original data can still be obtained.
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This is done using natural joins. A natural join is a type of join that creates a new table by combining rows that have matching values in two or more tables.
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Therefore, the Lossless-join property ensures that no information is lost in the decomposition and reconstruction process.
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