DATABASE SYSTEM CONCEPTS (LOOSELEAF)
7th Edition
ISBN: 9781260515046
Author: SILBERSCHATZ
Publisher: MCG
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Expert Solution & Answer
Chapter 2, Problem 14E
a.
Explanation of Solution
Query:
∏ID, person_name(σcompany_name=”BigBank”(works))
Explanation:
- The given query is used to find ID and name of each employee who works for BigBank in the employee
database ...
b.
Explanation of Solution
Query:
πID, person_name, city ( employee ⋈employee.id =works.id ( σcompany_name = "BigBank" ( works )) )
Explanation:
- The given query is used to find ID, name and city of residence of each employee who works for BigBank in the employee database...
c.
Explanation of Solution
Query:
πID, person_name, street, city ( σ(company_name = "BigBank" ∧ salary > 10000 ( works ⋈employee.id = works.id employee ))
Explanation:
- The given query is used to find ID, name, street address and city of residence of each employee who works for BigBank and earns more than $10000 in the employee database...
d.
Explanation of Solution
Query:
∏ID, person_name
(σemployee.city=company.city(employee ⋈employee.id=woks.id works
⋈works.company_name=company.company_name company))
Explanation:
Expert Solution & Answer
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Chapter 2 Solutions
DATABASE SYSTEM CONCEPTS (LOOSELEAF)
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