Consider the following database schema and specify the following queries or views in SQL. EMPLOYEE(SSN, name, salary, DNo, SupervisorSSN) DEPARTMENT (DNo, DeptName, MgrSSN) PROJECT(PNo, location, ProjName) WORKON (SSN, PNo, hours) Find the SSN and name of the employee who works on more than two projects. For each project, retrieve the PNo, ProjName, and the number of employees from 'Research' department who work on the project. Create a view called 'DEPT_INFO' that has the department name, the number of employees, and the total salary of the employees of the department.

Write SQL update statements to do the following on the database schema shown in Figure 1.i. Insert a new course, <‘Knowledge Engineering’, ‘CS4390’, 3, ‘CS’>.ii. Delete the record for the student whose name is ‘Smith’ and whose student number is 17.

EMPLOYEE Frame Minit Lname Sen Bdate Address Sex Salary Super sen Dno +444 DEPARTMENT Dname Dnumber Mor an Mgr start date DEPT LOCATIONS Dnumber Dlocation PROJECT Prame Prumber Plocation Dnum WORKS ON Ennn Pno Hoir Hours DEPENDENT Esen Dependent name Se Bdate Relationship Reforential integrity constraints displayed on the COMFWNY relational database schema. One possible database state for the COMPANY relational database schema. EMPLOYEE Fname Minit Lname John Frankin T Sex Salary 30000 333445555 5 M 40000 Jo00665555 F 25000 Joe7e54321 43000 J88Ge5556 San Bdate Address Super en Dno 123456789 1965-01-09 731 Fondren, Hounton, TX M 333445555 1955-12-08 638 Voas, Houston, TX Go0087777 1960-01-19 3321 Castle, Spring. TX 987654321 1941-06-20 291 Berry, Bellaire, TX Narayan 666884444 1962-09-15 975 Fire Oak, Humibile, TX M B Smith Wong Zelaya Wallace 5 Alicia 4 Jennifer F 38000 333445655 25000 333445555 M 25000 007654321 M 55000 NULL Ramesh English 453453453 1972-07-31 5631 Rice, Houston, TX F…

Assume the e-commercial database shown in the Appendix. Write the following queries in (a) relational algebra and (b) SQL. State your assumptions if the semantics is not clear. 1) Find the names of all students who have not taken any courses.     APPENDIX  STUDENTS(student id, first_name, last _name, email, major_code, class_year) COURSES(course id, course_name, course_description, credits, department_code) ENROLLMENTS(student id, course id, semester, grade) MAJORS(major code, major_name, department_code) DEPARTMENTS(department code, department_name)