Question: Given the database schema R a b c and a relation r on the
Given the database schema R (a, b, c), and a relation r on the schema R, write an SQL query to test whether the functional dependency b → c holds on relation r. Alsowrite an SQL assertion that enforces the functional dependency. Assume that no null values are present.
Answer to relevant QuestionsShow that the following decomposition of the schema R of Exercise 7.2 is not loss less-join decomposition:(A, B, C)(C, D, E).Give a loss less-join decomposition into BCNF of schema R of Exercise 7.2.Give an example of a relation schema R and a set of dependencies such that R is in BCNF, but is not in 4NF.Explain the distinction in meaning between edges in a DAG representing inheritance and a DAG representing object containment.Redesign the database of Exercise 9.1 into first normal form and fourth normal form. List any functional or multivalued dependencies that you assume. Also list all referential-integrity constraints that should be present in ...
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