SQL Exercise: Display the unique department with jobs

SQL employee Database: Exercise-10 with Solution

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10. From the following table, write a SQL query to find the unique department with jobs. Return department ID, Job name.

Sample table: employees

Pictorial Presentation:

Sample Solution:

SELECT DISTINCT dep_id,
                job_name
FROM employees ;

Sample Output:

 dep_id | job_name
--------+-----------
   3001 | MANAGER
   2001 | ANALYST
   3001 | SALESMAN
   1001 | MANAGER
   1001 | PRESIDENT
   2001 | MANAGER
   2001 | CLERK
   1001 | CLERK
   3001 | CLERK
(9 rows)

Explanation:

The said query in SQL that selects distinct combinations of the dep_id and job_name columns from the 'employees' table. The "DISTINCT" keyword ensures that each combination of dep_id and job_name appears only once in the result set, even if there are multiple employees with the same job and department.

A query like this might be used to get all unique job titles and departments in the company based on the "employees" table.

Relational Algebra Expression:

Relational Algebra Tree:

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Sample Database: employee

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