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Referring to Table 1, if interest rates rise by 5 percentage points, then bank profits (measured using gap analysis) will

Consider the following statements. [2 points] A functional dependency is checked by examining the instance of a relation. [2 points] The violation of a functional dependency is checked by examining the instance of a relation. [2 points] If an attribute has occurred on the right-hand side of some functional dependencies but not on the left-hand side of any functional dependency, it must be in the candidate keys. Give reasons for each statement whether it is correct or incorrect. Give the reason even if it is correct.

Given database schema: Faculty (fid, name, tenured, dname, salary, chairID)Department (dname, phoneNumber, numberOfFaculty)Course (fid, dname, semester, cname) Write a trigger (one trigger command) in SQL for the following statement: When a new record is inserted into Faculty, if the department does not exist in the Department table, then insert a record into Department with the same department name and the phone number equal to null. Additionally, when a record is deleted from Faculty, if the faculty member is tenured, then raise an error (use RAISE_APPLICATION_ERROR(-10000, ’error’)).

Exercise 1 (Armstrong Axioms, Functional Dependencies) [30 points]

Referring to Table 1, if interest rates rise by 5 percentage points, then bank profits (measured using gap analysis) will

Exercise 1 (Armstrong Axioms, Functional Dependencies) [30 points]

Given database schema: Faculty (fid, name, tenured, dname, salary, chairID)Department (dname, phoneNumber, numberOfFaculty)Course (fid, dname, semester, cname) Write an assertion check in SQL for the following condition: The salary of any faculty member cannot be greater than their chair’s salary.

Consider the relation schema R(A, B, C, D, E) and the set F = {AB → C, CD → E, DE → B} of functional dependencies. Find all candidate keys of R by using the tableau (7‐step) method. Explain the steps.

We decide to save time by sampling 1000 flights at random from a single month (instead of 250 from the whole data set) and then using the same process to get a confidence interval for the percentage of flights in the year that are delayed. Is this a good idea? Choose all the correct statements.

Given database schema: Faculty (fid, name, tenured, dname, salary, chairID)Department (dname, phoneNumber, numberOfFaculty)Course (fid, dname, semester, cname) Write an assertion check in SQL for the following condition: The salary of any faculty member cannot be greater than their chair’s salary.