Suppose an application programmer was supposed to write a query select * from r natural left outer join s; on relations r(A, B) and s(B, C), but instead wrote the query select * from r natural join s; a. Give sample data for r and s on which both queries would give the same result. b. Give sample data for r and s where the two queries would give different results, thereby exposing the error in the query.

Suppose an application programmer was supposed to write a query select * from r natural left outer join s; on relations r(A, B) and s(B, C), but instead wrote the query select * from r natural join s; a. Give sample data for r and s on which both queries would give the same result. b. Give sample data for r and s where the two queries would give different results, thereby exposing the error in the query.

Oracle 12c: SQL

3rd Edition

ISBN:9781305251038

Author:Joan Casteel

Publisher:Joan Casteel

Chapter3: Table Creation And Management

Section: Chapter Questions

Problem 6RQ: What happens to the existing rows of a table if the DEFAULT value of a column is changed?

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