The Student Database Student sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 Class deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz Enroll siddeptcnumsec 301CS EE CS EE18301 GradStudent sidnameaddrageGPA 501Raymond180 Westwood Amy301 Wilshire Jack220 Gayley Dan220 Gayley253.3

The Selection Operator   Give me information of students under the age of 18   age<18 (Student) sidnameaddrageGPA 303Elaine301 Wilshire James183 Westwood173.6 sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1

The Projection Operator   Give me the name, address, and GPA of all the students   name, addr, GPA (Student)   name, GPA, addr (Student) sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 nameaddrGPA John183 Westwood2.1 Elaine301 Wilshire3.9 James183 Westwood3.6 Esther421 Gayley3.1 nameGPAaddr John Westwood Elaine Wilshire James Westwood Esther Gayley

Sample Query  Give me the SID and GPA for students under the age of 18   sid, GPA (  age<18 (Student)) sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 sidnameaddrageGPA 303Elaine301 Wilshire James183 Westwood173.6 sidGPA

The Cross Product Operator   Give me all combinations of students and the enrollment of students  Student  Enroll = (Student.sid, name, addr, age, GPA, Enroll.sid, dept, cnum, sec) Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE John183 Westwood CS John183 Westwood EE Elaine301 Wilshire CS Elaine301 Wilshire EE Elaine301 Wilshire CS Elaine301 Wilshire EE James183 Westwood CS James183 Westwood EE James183 Westwood CS James183 Westwood EE Esther421 Gayley CS Esther421 Gayley EE Esther421 Gayley CS Esther421 Gayley EE18301 Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE John183 Westwood CS John183 Westwood EE18301 Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE John183 Westwood CS John183 Westwood EE Elaine301 Wilshire CS Elaine301 Wilshire EE Elaine301 Wilshire CS Elaine301 Wilshire EE18301 Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE John183 Westwood CS John183 Westwood EE Elaine301 Wilshire CS Elaine301 Wilshire EE Elaine301 Wilshire CS Elaine301 Wilshire EE James183 Westwood CS James183 Westwood EE James183 Westwood CS James183 Westwood EE18301 Student sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 Enroll siddeptcnumsec 301CS EE CS EE18301

Selecting on Cross Products  Give me all the information of enrolled students   Student.sid = Enroll.sid (Student  Enroll) Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE Elaine301 Wilshire CS James183 Westwood EE18301 Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE John183 Westwood CS John183 Westwood EE Elaine301 Wilshire CS Elaine301 Wilshire EE Elaine301 Wilshire CS Elaine301 Wilshire EE James183 Westwood CS James183 Westwood EE James183 Westwood CS James183 Westwood EE Esther421 Gayley CS Esther421 Gayley EE Esther421 Gayley CS Esther421 Gayley EE18301 Student sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 Enroll siddeptcnumsec 301CS EE CS EE18301

Sample Query  Give me the name and addresses of students taking CS courses whose GPA is below 3.0   name, addr (  dept = ‘CS’  GPA < 3.0  Student.sid = Enroll.sid (Student  Enroll)) Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE John183 Westwood CS John183 Westwood EE Elaine301 Wilshire CS Elaine301 Wilshire EE Elaine301 Wilshire CS Elaine301 Wilshire EE James183 Westwood CS James183 Westwood EE James183 Westwood CS James183 Westwood EE Esther421 Gayley CS Esther421 Gayley EE Esther421 Gayley CS Esther421 Gayley EE18301 Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE Elaine301 Wilshire CS James183 Westwood EE18301 Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS John183 Westwood EE30101 Student.sidnameaddrageGPAEnroll.siddeptcnumsec 301John183 Westwood CS14301 nameaddr John183 Westwood Student sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 Enroll siddeptcnumsec 301CS EE CS EE18301

The Join Operator  ClassEnroll   Class.dept = Enroll.dept  Class.cnum = Enroll.cnum  Class.sec = Enroll.sec (Class  Enroll) Enroll siddeptcnumsec 301CS EE CS EE18301 Class deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz C.deptC.cnumC.sectitleinstructorsidE.deptElcnumE.sec CS14301DB SystemsJohn Cho301CS14301 CS14301DB SystemsJohn Cho301EE30101 CS14301DB SystemsJohn Cho303CS11201 CS14301DB SystemsJohn Cho401EE18301 CS11201ModelingDick Muntz301CS14301 CS11201ModelingDick Muntz301EE30101 CS11201ModelingDick Muntz303CS11201 CS11201ModelingDick Muntz401EE18301 EE30101SignalJames Dean301CS14301 EE30101SignalJames Dean301EE30101 EE30101SignalJames Dean303CS11201 EE30101SignalJames Dean401EE18301 EE18301MechanicsDick Muntz301CS14301 EE18301MechanicsDick Muntz301EE30101 EE18301MechanicsDick Muntz303CS11201 EE18301MechanicsDick Muntz401EE18301 C.deptC.cnumC.sectitleinstructorsidE.deptE.cnumE.sec CS14301DB SystemsJohn Cho301CS14301 CS11201ModelingDick Muntz303CS11201 EE30101SignalJames Dean301EE30101 EE18301MechanicsDick Muntz401EE18301

The Theta-Join Operator   Class Class.cnum = Enroll.cnum  Enroll.dept = ‘CS’ Enroll   Class.cnum = Enroll.cnum  Enroll.dept = ‘CS’ (Student  Enroll) Enroll siddeptcnumsec 301CS EE CS EE18301 Class deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz C.deptC.cnumC.sectitleinstructorsidE.deptE.cnumE.sec CS14301DB SystemsJohn Cho301CS14301 CS14301DB SystemsJohn Cho301EE30101 CS14301DB SystemsJohn Cho303CS11201 CS14301DB SystemsJohn Cho401EE18301 CS11201ModelingDick Muntz301CS14301 CS11201ModelingDick Muntz301EE30101 CS11201ModelingDick Muntz303CS11201 CS11201ModelingDick Muntz401EE18301 EE30101SignalJames Dean301CS14301 EE30101SignalJames Dean301EE30101 EE30101SignalJames Dean303CS11201 EE30101SignalJames Dean401EE18301 EE18301MechanicsDick Muntz301CS14301 EE18301MechanicsDick Muntz301EE30101 EE18301MechanicsDick Muntz303CS11201 EE18301MechanicsDick Muntz401EE18301 C.deptC.cnumC.sectitleinstructorsidE.deptE.cnumE.sec CS14301DB SystemsJohn Cho301CS14301 CS11201ModelingDick Muntz303CS11201

The Union Operator   Give me the SIDs of all students   sid (Student  GradStudent) Student sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 GradStudent sidnameaddrageGPA 501Raymond180 Westwood Amy301 Wilshire Jack220 Gayley Dan220 Gayley253.3 sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley Raymond180 Westwood Amy301 Wilshire Jack220 Gayley Dan220 Gayley253.3 sid

The Set-Difference Operator –  Give me the department, course number, and section of all classes without any enrolled students   dept, cnum, sec (Class) –  dept, cnum, sec (Enroll) Class deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz Enroll siddeptcnumsec 301CS EE CS EE18301 deptcnumsec CS14301 CS11201 EE30101 EE18301 deptcnumsec CS14301 EE30101 CS11201 EE18301 deptcnumsec

The Set-Intersection Operator   Give all the instructors who teaches both CS and EE classes   instructor (  dept=’CS’ (Class))   instructor (  dept=’EE’ (Class)) Class deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz instructor John Cho Dick Muntz instructor James Dean Dick Muntz instructor Dick Muntz

The Rename Operator   Give me pairs of student names who live at the same address   R.name > S.name (  name, name (  R.addr = S.addr (  R (Student)   S (Student) ) ) ) Student sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 R.sidR.nameR.AddrR.AgeR.GPAS.SidS.NameS.AddrS.AgeS.GPA 301John183 Westwood John183 Westwood John183 Westwood Elaine301 Wilshire John183 Westwood James183 Westwood John183 Westwood Esther421 Gayley Elaine301 Wilshire John183 Westwood Elaine301 Wilshire Elaine301 Wilshire Elaine301 Wilshire James183 Westwood Elaine301 Wilshire Esther421 Gayley James183 Westwood John183 Westwood James183 Westwood Elaine301 Wilshire James183 Westwood James183 Westwood James183 Westwood Esther421 Gayley Esther421 Gayley John183 Westwood Esther421 Gayley Elaine301 Wilshire Esther421 Gayley James183 Westwood Esther421 Gayley Esther421 Gayley203.1 R.sidR.nameR.AddrR.AgeR.GPAS.SidS.NameS.AddrS.AgeS.GPA 301John183 Westwood John183 Westwood John183 Westwood James183 Westwood Elaine301 Wilshire Elaine301 Wilshire James183 Westwood John183 Westwood James183 Westwood James183 Westwood Esther421 Gayley Esther421 Gayley203.1 R.nameS.Name John James Elaine JamesJohn James Esther R.nameS.Name JamesJohn

The Division Operator /  Give me the SIDs of students who are enrolled in all of the CS classes   sid (Student) –  sid (  sid (Student   dept, cnum, sec (  dept=’CS’ (Class))) – Enroll) Student sidnameaddrageGPA 301John183 Westwood Elaine301 Wilshire James183 Westwood Esther421 Gayley203.1 Class deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz Enroll siddeptcnumsec 301CS EE CS EE18301

The Division Operator /  Give me the SIDs of students who are enrolled in all of the CS classes   sid (Student) –  sid (  sid (Student)   dept, cnum, sec (  dept=’CS’ (Class) ) – Enroll) ) deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz EE30101SignalJames Dean EE18301MechanicsDick Muntz deptcnumsectitleinstructor CS14301DB SystemsJohn Cho CS11201ModelingDick Muntz siddeptcnumsec 301CS CS CS CS CS CS CS CS11201 deptcnumsec CS14301 CS11201 sid siddeptcnumsec 301CS EE CS EE18301 siddeptcnumsec 303CS CS CS CS CS11201 sid sid 301 sid