Consider the relational database of Figure 1. What are the appropriate primary keys? employee (personname, street, city) works (person_raте, соmpany-лamе, salary) соmpany (compапy лате, сity)

Consider the relational database of Figure 1. What are the appropriate primary keys? employee (personname, street, city) works (person_raте, соmpany-лamе, salary) соmpany (compапy лате, сity)

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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Suppose you have the following relational database scheme for a real estate agency: Real Estate Office (officeID, street, city, postalCode) Employee (employee ID, name, surname, position, gender, salary, officeID) For rentMulk (estateD, street, city, postalCode, type, number of rooms, rent, estateOwnerID, employeeID, officeID) Customer (customerID, name, surname, tel, maxrent) estateOwner (estateHeaderID, name, surname, address, tel) estateshow (customerID, estateID, showTime, comment) Record (customerID, officeID, employeeID, recordDate) Firstly, determine the appropriate primary key for each relationship. Then create the appropriate queries using relational algebra and SQL. List the ID, street, city and rent information of the properties managed by the employees in the office located on "Fifth Street" street. List all the cities with offices but no rental properties. List the names and comments of all customers who have viewed a rental property. List the first and last names of…
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