Chapter 9.3, Problem 8QC

Consider the following relational schema and briefly answer the questions that follow:   Emp(eid: integer, ename: string, age: integer, salary: real)  Works(eid: integer, did: integer, pct_time: integer)  Dept(did: integer, budget: real, managerid: integer)      a. Define a table constraint on Dept that will ensure that all managers have age > 30. b. Write SQL statements to delete all information about employees whose salaries exceed that of the manager of one or more departments that they work in. Be sure to ensure that all the relevant integrity constraints are satisfied after your updates.

Consider the following relations:     Student(snum: integer, sname: string, rmajor: string,          level: string, age: integer)   Class(cname: string, meets_at: time, room: string, fid: integer)   Enrolled(snum: integer, cname: string)   Faculty(fid: integer, fname: string, deptid: integer)     The meaning of these relations is straightforward; for example, Enrolled has one record per student-class pair such that the student is enrolled in the class.     2. Express each of the following integrity constraints in SQL unless it is implied by the primary and foreign key constraint; if so, explain how it is implied. If the constraint cannot be expressed in SQL, say so. For each constraint, state what operations (inserts, deletes, and updates on specific relations) must be monitored to enforce the constraint.   (a) Every faculty member must teach at least two courses. (b) Every student must be enrolled in the course called 'Math101'. (c) A student cannot add more than two courses at a time…

Consider the following relational schema. An employee can work in more than one department; the pct_time field of the Works relation shows the percentage of time that a given employee works in a given department.   Emp(eid: integer, ename: string, age: integer, salary: real)  Works(eid: integer, did: integer, pct_time: integer)  Dept(did: integer, budget: real, managerid: integer)      Write the following queries in SQL:   a. Print the name of each employee whose salary exceeds the budget of all of the departments that he or she works in. b. Find the enames of managers who manage only departments with budgets larger than $1 million, but at least one department with budget less than $5 million.