Please clear answer (question 6) Question 5 (4 points): What kind of statistics

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Please clear answer (question 6)

Question 5 (4 points): What kind of statistics that allows us to get a better estimate for point previous question. Show a small example including multiple brands and products. coudy Question 6: Library Books (Book-ISBN, Library ID, titte, lib_address, book_title, no_of_copies) Consider the relation above about library books with the following FDs: Book ISBN, Library_ID > no_of_copies Book ISBN book title Library ID lib_address lib address County County book_title lib address Book Library_ID C++ Prog. ISBN Multnomah 11 Burnside L1 Washington Data Structures 123 23 185th Ave. Intro. Databases L2 Multnomah 456 23 Powell Blvd. 789 no_of_copies 3 LI a) Which FD is not enforced in the database instance above? (1 point) b) Fix the data so the FD in point a is enforced. You only need to rewrite one rowo ok title) is satisfied. The query should c) Write one SQL query to test if the FD (Book ISBN book_title) is satisfied return an empty result if the FD is satisfied (enforced). (3 points)

Explanation / Answer

a.

Library_Id -> Library_Address is not enforced in the table.

As functional dependency uniquely determine another attribute but here, L1 is pointing to two different address

b.

To fix the functional dependency we need same address for L1 or we need different library id for both the address.

So we will fix row 3 and it will look like -

789 | L1| 11 Burnside | Multnomah | Intro. Database | 3

c.

d.

It will divide into 2 tables -

One with -

Book_ISBN Library_Id Library_address Book_title No_Of_Copies

other with -

Book_ISBN Library_Id Country

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