Consider the following bcnf schema and a portion of a simple corporate database (type
information is not relevant to this question and is omitted):
emp(eid, ename, addr, sal, age, yrs, deptid)
dept(did, dname, floor, budget)
suppose you know that the following queries are the six most common queries in the workload
for this corporation and that all six are roughly equivalent in frequency and importance:
 list the id, name and address of employees in a user-specified age range
 list the id, name and address of employees who work in the department with a userspecified department name
 list the id and address of employees with a user- specified employee name
 list the overall average salary for employees
 list the average salary for employees of each age; that is, for each age in the database,
list the age and the corresponding average salary.
 list all the department information, ordered by department floor numbers.