Consider the following relations: emp(empno, ename, age, job, salary, dob, doj, deptno) Find employees who earns highest salary for their job (A)select ename, job, salary from emp where sal in (select max(sal) from emp group by job); (B) select ename, job, salary from emp where (job, sal) in(select job, max(sal) from emp group by job); (C) select ename, job, salary from emp where (job, sal) = (select job, max(sal) from emp group by job); (D) Both B and C

Consider the following relations: emp(empno, ename, age, job, salary, dob, doj, deptno) Find employees who earns highest salary for their job (A)select ename, job, salary from emp where sal in (select max(sal) from emp group by job); (B) select ename, job, salary from emp where (job, sal) in(select job, max(sal) from emp group by job); (C) select ename, job, salary from emp where (job, sal) = (select job, max(sal) from emp group by job); (D) Both B and C

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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PLEASE TYPE IF POSSIBLE OR WRTIE ELIGIBLY Consider a relation X with six attributes WYSMFE where WS is a composite primary key for X. Assume X has the following functional dependencies (X is one table with the attributes W, Y, S, M, F, E): WS è YMFE S è YME E è M In what normal form is relation X? Explain why? Is it possible to decompose X into a number of relations in order to achieve a higher normal form? Explain how (this means using English sentences and a diagram showing the final relation(s)).
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