Consider a schema R = {A,B,C,D,E}and the following set of functional dependencies: {AB → C,C → D,D → BE} Is R in Boyce-Codd normal form? Justify your answer.

Given the reation R (A, B, C, D , E), with functional dependencies: A, B -> C D, E -> C B -> D Could you explain why this is not functional dependency preserving? Also could you work out the BCNF for this?

Vector space classification methods frequently fail when applied to problem sets with nominal feature sets alone. What do you think of the statement? Using ML, how would you classify nominal data? Answer each of the above queries in detail.

The database interface of a library allows searching only for a single attribute (such as Title or Author ) in each query. Your friend decided to extend it’s functionality and wrote an algorithm that allows searching for books that satisfy multiple predicates over single attributes in conjunction. He tells you the algorithm reuses the already implemented query functionality and works by intersecting the results ( book id’s ) of queries over single attributes.Which of the following assumptions on your friend’s algorithm are plausible?a) Its worst-case run-time necessarily increases exponentially with respect to the number of attributes in the query.b) Its worst-case run-time depends on the length of the longest result of the single-attribute queries.c) It might be implemented using an join.d) It might be implemented using sorting.