Jika terdapat SQL query berikut:

SELECT D.Dname
FROM DEPARTMENT D, EMPLOYEE E
WHERE D.Dnumber = E.Dno AND E.Salary 50000;

Maka, relational algebra yang memberikan biaya eksekusi minimal adalah:

Question

Jika terdapat SQL query berikut: 
   
 SELECT D.Dname   
 FROM DEPARTMENT D, EMPLOYEE E   
 WHERE D.Dnumber = E.Dno AND E.Salary > 50000; 
   
 Maka, relational algebra yang memberikan  biaya eksekusi minimal  adalah:

Accepted Answer

πD.Dname​((πE.Dno​(σE.Salary>50000​(E)))⋈D.Dnumber=E.Dno​(πD.Dname,D.Dnumber​(D)))

Answer

πD.Dname​(σE.Salary>50000​(E)⋈D.Dnumber=E.Dno​(πD.Dname,D.Dnumber​(D)))

Answer

πD.Dname​(D⋈D.Dnumber=E.Dno∧E.Salary>50000​E)

Answer

πD.Dname​(σD.Dnumber=E.Dno​(σE.Salary>50000​(E)×D))

Crowdly

Jika terdapat SQL query berikut: SELECT D.Dname FROM DEPARTMENT D, EMP...

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