Question: 07. Consider a database containing two relations: R(A,B,C) and S(D.E.F). For each of three (your choice) of the 12 rewriting rules for relational algebra expression,

07. Consider a database containing two relations: R(A,B,C) and S(D.E.F). For

07. Consider a database containing two relations: R(A,B,C) and S(D.E.F). For each of three (your choice) of the 12 rewriting rules for relational algebra expression, give an example pair of relational algebra expressions involving R and S such that the rule rewrites one expression to the other expression, and give another example pair to show the rewriting rule cannot be used since some of the conditions for the rule are not satisfied

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