Use the following schema to write relational algebra statements for the questions that follow. The primary keys are underlined in the schema:
STUDENT(Ssn, Name, Major, DOB)
COURSE(Cnum, Cname, Dept)
ENROLL(Ssn, Cnum, Semester, Grade)
BOOK_ADOPTION(Cnum, Semester, ISBN)
TEXTBOOK(ISBN, Title, Publisher, Author)
Specify the following queries in relational algebra:
- List the course number taken by all students named 'John Smith' in winter 1999 (i.e., Semester = 'W99').
- Produce a list of textbooks (include Course#, ISBN, Title) for courses offered by the Computer Science Department (i.e., Dept = 'CS').
- List any department that has its adopted books published by 'BC Publishing'.
- Find the names of students who have not been enrolled in any course.
- Find all the textbooks that were authored by Mike Wilkins.