I Want The Solution To Be Handwritten Please 1 (119.81 KiB) Viewed 27 times
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For the following schema: EMPLOYEE Fname Minit Lname Ssn Bdate DEPARTMENT Dname Dnumber Mgr_ssn Mgr_start_date DEPT_LOCATIONS Dnumber Dlocation PROJECT Pname Pnumber Plocation Dnum WORKS ON Essn Pno Hours DEPENDENT Essn Dependent_name Sex Bdate Relationship Consider The Following SQL queries Address Sex Salary Super_ssn Dno
Q4: (SELECT DISTINCT Pnumber FROM PROJECT, DEPARTMENT, EMPLOYEE WHERE Dnum=Dnumber AND Mgr_ssn=Ssn AND Lname='Smith') UNION (SELECT DISTINCT Pnumber FROM PROJECT, WORKS_ON, EMPLOYEE WHERE Pnumber=Pno AND Essn=Ssn AND Lname='Smith' ); Q5: SELECT Pnumber, Pname, COUNT (*) FROM PROJECT, WORKS_ON, EMPLOYEE WHERE Pnumber=Pno AND Ssn Essn AND Dno=5 GROUP BY Pnumber, Pname; (a) Draw the canonical query trees for each of these queries. (b) Show how the query tree is optimized for each of these quires using Heuristics in Query Optimization.
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