Question

Consider the following GRADEBOOK relational schema describing the data for a grade

book of a particular instructor (Note: The attributes A, B, C, and D store grade cutoffs.)

catalog(cno,ctitle)

students(sid,fname,lname,minit)

courses(term,secno,cno,A,B,C,D)

enrolls(sid,term,secno)

Specify and execute the following queries using the RA interpreter on the GRADEBOOK

database schema.

a. Retrieve the names of students enrolled in the ‘Automata’ class in the term of Fall

1996.

b. Retrieve the SID values of students who have enrolled in CSc226 as well as CSc227.

c. Retrieve the SID values of students who have enrolled in CSc226 or CSc227.

d. Retrieve the names of students who have not enrolled in any class.

e. Retrieve the names of students who have enrolled in all courses in the catalog table.

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I need help on implementing this Querys using the relational algebra interpreter in my windows command prompt

Command Prompt - java edu.gsu.cs.ra.RA company C:\Userslalfre>cd Desktop /Database systems/ch2 C:\Users\alfre\Desktop\Database systems\ch2>java edu.gsu.cs.ra.RA company RA>

Answer 1

b) Retsieve the SID values อt studen who have engo-"ed in CSL 226 as wel, as C SC 22구 solgfen Pefect s.cuprafeet [ sid, s eno] C Select (secno -Csc2 6 Cennolls)) select [secnos CSCL27.J (engo lus)