Properties of RelationalDecompositions (2) Relation Decomposition andInsufficiency of Normal Forms (cont.): Decomposition: The process of decomposing the universal relationschema R into a set of relation schemas D ={R1,R2, …, Rm} that will become the relationaldatabase schema by using the functionaldependencies. Attribute preservation condition: Each attribute in R will appear in at least onerelation schema Ri in the decomposition so that noattributes are “lost”.
Question
Properties of RelationalDecompositions (2) Relation Decomposition andInsufficiency of Normal Forms (cont.): Decomposition: The process of decomposing the universal relationschema R into a set of relation schemas D ={R1,R2, …, Rm} that will become the relationaldatabase schema by using the functionaldependencies. Attribute preservation condition: Each attribute in R will appear in at least onerelation schema Ri in the decomposition so that noattributes are “lost”.
Solution
To understand the properties of relational decompositions, we need to first define what decomposition is. Decomposition is the process of breaking down a universal relation schema, denoted as R, into a set of relation schemas, denoted as D = {R1, R2, ..., Rm}. These relation schemas will then form the relational database schema.
One important condition in decomposition is the attribute preservation condition. This condition ensures that each attribute in the original relation schema R will appear in at least one of the relation schemas Ri in the decomposition. This means that no attributes will be "lost" during the decomposition process.
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