| | 79 | |
| | 80 | * '''π_{CoverImage, Title, Genre, FirstName, LastName, quarter, loan_count} |
| | 81 | (σ_{EXTRACT(QUARTER FROM LoanDate) = 4} |
| | 82 | ((Book ⨝{Book.BookID = Book_Copies.BookID} Book_Copies) |
| | 83 | ⟕{Book_Copies.CopyID = Loan.BookCopyID} Loan |
| | 84 | ⨝{Book.BookID = Book_Author.BookID} Book_Author |
| | 85 | ⨝{Book_Author.AuthorID = Author.AuthorID} Author) |
| | 86 | γ_{Book.BookID, Book.Title, Book.CoverImage, Book.Genre, Author.FirstName, Author.LastName, EXTRACT(QUARTER FROM Loan.LoanDate)} COUNT(Loan.LoanID) → loan_count |
| | 87 | τ_{loan_count ASC} ρ_{LIMIT 5})'''' |
| | 88 | |
| | 89 | * π (CoverImage, Title, Genre, FirstName, LastName, quarter, loan_count) |
| | 90 | | |
| | 91 | τ (ORDER BY loan_count ASC, LIMIT 5) |
| | 92 | | |
| | 93 | γ (GROUP BY BookID, Title, CoverImage, Genre, FirstName, LastName, quarter, COUNT(LoanID) → loan_count) |
| | 94 | | |
| | 95 | σ (EXTRACT(QUARTER FROM LoanDate) = 4) |
| | 96 | | |
| | 97 | ┌───────────────────────────────────────────⨝──────────────────────────────────────────────┐ |
| | 98 | | | |
| | 99 | (Book ⨝ Book_Copies) (Loan ⟕ Book_Copies.CopyID = Loan.BookCopyID) |
| | 100 | | | |
| | 101 | (Book ⨝ Book_Author) (Loan Table) |
| | 102 | | |
| | 103 | (Book_Author ⨝ Author) |
| | 104 | | |
| | 105 | (Author Table) |
| | 106 | |