SQL exercises on employee Database: List the manager no and the number of employees working for those managers in ascending order on manager id

SQL employee Database: Exercise-96 with Solution

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96. From the following table, write a SQL query to list the managers and number of employees work under them. Sort the result set in ascending order on manager. Return manager ID and number of employees under them.

Sample table: employees

Sample Solution:

SELECT w.manager_id,
       count(*)
FROM employees w,
     employees m
WHERE w.manager_id = m.emp_id
GROUP BY w.manager_id
ORDER BY w.manager_id ASC;

Sample Output:

  manager_id | count
------------+-------
      65646 |     2
      66928 |     5
      67832 |     1
      67858 |     1
      68319 |     3
      69062 |     1
(6 rows)

Relational Algebra Expression:

Relational Algebra Tree:

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Sample Database: employee

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