Description
Relational Algebra Expressions (PART A)
Product (make, model, type)
PC (model, speed, ram, hd, price)
Laptop (model, speed, ram, hd, screen, price)
Printer (model, color, type, price)
Given the above schema from the RELAX Database example set. Solve all queries
below using only select, project, Cartesian product, and natural join. Do not use thetajoin, set operations, renaming or assignment. Provide the relational algebra
expressions and the screenshots after executing each query on RELAX.
1. Find all prices for laptops that are above R1000.
2. Find all printers that are laser and that are color printers.
3. Find all printers that are below R500 that are inkjet printers.
4. Find all PC’s that have speed equal to 3.2 and HD size above 200
5. Project product model only for all Laptops that are Maker A or
Maker B.
Relational Algebra Expressions (PART B)
Employee (Name, EmpId, DeptName)
Dept (DeptName, Manager)
Completed (Student, Task)
DBProject (Task)
Car (CarModel, CarPrice)
Boat (BoatModel, BoatPrice)
Given the above Wikipedia schema from the RELAX Database example set. Solve all
queries below. Provide the relational algebra expressions and the screenshots after
executing each query on RELAX.
1. Find all Employees who work finance.
2. Find all boats with prices that are above R3000.
3. Join both Employee and Car and project cars for employees that
are from the ‘sales’ department.
4. From Completed find all students who completed ‘Compiler 1’, and
‘Database 1’.
5. From Completed find all students who completed ‘Compiler 1’, or
‘Database 2’.
