SQL Exercise: Employees and managers name separated by a string

SQL employee Database: Exercise-19 with Solution

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19. From the following table, write a SQL query to separate the names of employees and their managers by the string 'works for'.

Sample table: employees

Pictorial Presentation:

Sample Solution:

SELECT e.emp_name || ' works for ' || m.emp_name
FROM employees e,
     employees m
WHERE e.manager_id = m.emp_id;

Sample Output:

         ?column?
--------------------------
 BLAZE works for KAYLING
 CLARE works for KAYLING
 JONAS works for KAYLING
 SCARLET works for JONAS
 FRANK works for JONAS
 SANDRINE works for FRANK
 ADELYN works for BLAZE
 WADE works for BLAZE
 MADDEN works for BLAZE
 TUCKER works for BLAZE
 ADNRES works for SCARLET
 JULIUS works for BLAZE
 MARKER works for CLARE
(13 rows)

Explanation:

The provided query in SQL that selects the names of all employees along with their corresponding manager's name by joining the 'employees' table to itself using the "manager_id" and "emp_id" columns.

The "||" operator concatenates the "emp_name" column of the employee with the string " works for " and the "emp_name" column of their manager.

The WHERE clause includes the employees who have a corresponding manager in the 'employees' table.

Practice Online

Sample Database: employee

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