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Discussion Forum

Que. Given the following schema:

employees(emp-id, first-name, last-name, hire-date, dept-id, salary)
departments(dept-id, dept-name, manager-id, location-id)

You want to display the last names and hire dates of all latest hires in their respective departments in the location ID 1700. You issue the following query:

SQL> SELECT last-name, hire-date
FROM employees
WHERE (dept-id, hire-date) IN
(SELECT dept-id, MAX(hire-date)
FROM employees JOIN departments USING(dept-id)
WHERE location-id = 1700
GROUP BY dept-id);

What is the outcome?
a. It executes but does not give the correct result
b. It executes and gives the correct result
c. generates an error because of pairwise comparison
d. It generates an error because the GROUP BY clause cannot be used with table joins in a subquery
Answer:It executes and gives the correct result
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