subject
Computers and Technology, 11.10.2020 23:01 artbydi

Consider the following relational schema for a library: member(memb_no, name, dob)
books(isbn, title, authors, publisher)
borrowed(memb_no, isbn, date)
Write the following queries in relational algebra.
A. Find the names of members who have borrowed any book published by "McGraw-Hill".
B. Find the names of members who have borrowed all books published by "McGraw-Hill".
C. Find the name and membership number of members who have borrowed more than five different books published by "McGraw-Hill".
D. For each publisher, find the name and membership number of members who have borrowed more than five books of that publisher.
E. Find the average number of books borrowed per member. Take into account that if a member does not borrow any books, then that member does not appear in the borrowed relation at all.

ansver
Answers: 2

Another question on Computers and Technology

question
Computers and Technology, 23.06.2019 06:00
What makes myhexadecimalnumber a child of mynumber? which methods does myhexadecimalnumber inherit directly from the mynumber class? what can an instance of the mynumber class do? what can an instance of the myhexadecimalnumber class do? which methods are overridden? why are they overridden? how many examples of overloading are there? why was this done? where is the super keyword used? what is it doing? why isn’t the incoming value set immediately in the second myhexadecimalnumber constructor? how many examples can you find of an inherited method being called?
Answers: 1
question
Computers and Technology, 24.06.2019 00:10
Read each statement below. if the statement describes a peer-to-peer network, put a p next to it. if the statement describes a server-based network, put an s next to it. p - peer-to-peer s - server-based
Answers: 1
question
Computers and Technology, 24.06.2019 10:20
Write a program that keeps asking the user for new values to be added to a list until the user enters 'exit' ('exit' should not be added to the list). these values entered by the user are added to a list we call 'initial_list'. then write a function that takes this initial_list as input and returns another list with 3 copies of every value in the initial_list. finally, inside print out all of the values in the new list. for example: input: enter value to be added to list: a enter value to be added to list: b enter value to be added to list: c enter value to be added to list: exit output: a b c a b c a b c note how 'exit' is not added to the list. also, your program needs to be able to handle any variation of 'exit' such as 'exit', 'exit' etc. and treat them all as 'exit'.
Answers: 2
question
Computers and Technology, 24.06.2019 12:00
Match the function to its purpose. fast worth 50pts.
Answers: 1
You know the right answer?
Consider the following relational schema for a library: member(memb_no, name, dob)
books(isb...
Questions
question
Mathematics, 31.01.2021 18:50
question
Mathematics, 31.01.2021 18:50
question
Engineering, 31.01.2021 18:50
Questions on the website: 13722361