Provide an expression in relational algebra

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Reference no: EM1367127

Q1) person(person name, street, city) // records about all people
works(person name, company name, annual salary) // records about employed people
company(company name, founded) // companies and years when they were founded
company location(company name, city) // companies and cities where they have oces
managed by(person name, manager name) // employed people and their managers

Give an expression in relational algebra for each of the following queries:

(a) Find the maximum salary of all employees who are not managers.

(b) Give all the managers in the database a 10 percent salary raise. Give all the other employees a 5 percent salary raise.

Reference no: EM1367127

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