Lossless-Join Decomposition

In computer science the concept of a Lossless-Join Decomposition is central in removing redundancy safely from databases while preserving the original data.

Can also be called Nonadditive. If you decompose a relation ${\displaystyle R}$ into relations ${\displaystyle R_{1}}$ and ${\displaystyle R_{2}}$ you will guarantee a Lossless-Join if ${\displaystyle R_{1}}$x${\displaystyle R_{2}}$ = ${\displaystyle R}$.

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