Display the list of all departments, with the total number of instructors in each department, without using scalar subqueries. make sure to correctly handle departments with no instructors.
Is this the right answer:
select department.dept_name
from department natural left outer join
instructor.ID;
No, that is not the correct answer. The provided query will only display the department names. It does not include the total number of instructors in each department, nor does it correctly handle departments with no instructors.
To achieve the desired result, you can use a combination of JOIN, GROUP BY, and COUNT functions. Here is the correct query:
```sql
SELECT department.dept_name, COUNT(instructor.ID) AS total_instructors
FROM department
LEFT JOIN instructor ON department.dept_id = instructor.dept_id
GROUP BY department.dept_name;
```
In this query, we are joining the "department" table with the "instructor" table using the "dept_id" column as the common link. By using a LEFT JOIN, we ensure that all departments are included in the result, even if they have no instructors.
The GROUP BY clause is then used to group the result by department name. The COUNT(instructor.ID) function is applied to calculate the total number of instructors in each department.
This query will give you the list of all departments along with the total number of instructors in each department, correctly handling departments with no instructors.