Part $2$ Problem $4(20$ Points$)$:

Consider the database $($key attributes are underlined$)$

Student$($Sid$,$ Sname, Major, Gpa$)$

Department $($Dcode$,$ Dname, School, Address, Tel$)$

School$($Scode$,$ Sname, Dean, Address, Mission$)$

Use heuristics to optimize the following query. Show your answers in two possible optimized queries:

Student Department Scode School $\{$:$)$

Problem $5(30$ Points$)$:

Consider the database $($key attributes are underlined$)$

Student$($Sid:$10,$ Sname: $30,$ Major: $10,$ Gpa: $5)$

Department $($Dcode: $10,$ Dname: $30,$ School: $10,$ Address: $50,$ Tel: $10)$

School$($Scode: $10,$ Sname: $30,$ Dean: $30,$ Address: $50,$ Mission: $100)$

Assume also these two foreign key constraints:

Student.Major $$ Department.Dcode

Department.School $$ School.Scode