Let R. be a relation with attributes ABCD. Consider the conjunctive SQL query: select x.B, x.C,...

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Let R. be a relation with attributes ABCD. Consider the conjunctive SQL query: select x.B, x.C, x.D from R. x, R y, Rz where x.B y.B and z.B = 8 and x.A = x.C = and x.D= y.C and z.Ay.C and z.C = x.A (i) (2 points) Construct the pattern corresponding to the query. (ii) (2 points) Is the pattern constructed in (i) minimal? (Explain) (ii) (5 points) Minimize the pattern in (i) knowing that the query is only applied to databases satisfying the FD's. BA, AC, C → D Show the intermediate steps. (iii) (1 point) Construct from the minimized pattern a corresponding min- imized SQL query. Let R. be a relation with attributes ABCD. Consider the conjunctive SQL query: select x.B, x.C, x.D from R. x, R y, Rz where x.B y.B and z.B = 8 and x.A = x.C = and x.D= y.C and z.Ay.C and z.C = x.A (i) (2 points) Construct the pattern corresponding to the query. (ii) (2 points) Is the pattern constructed in (i) minimal? (Explain) (ii) (5 points) Minimize the pattern in (i) knowing that the query is only applied to databases satisfying the FD's. BA, AC, C → D Show the intermediate steps. (iii) (1 point) Construct from the minimized pattern a corresponding min- imized SQL query.

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i Construct the pattern corresponding to the query The given SQL query can be translated into a patt... View the full answer