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SQL exercises on employee Database: List the name of departments where atleast 2 employees are working in that department

SQL employee Database: Exercise-102 with Solution

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102. From the following tables, write a SQL query to find those departments where at least two employees work. Return department name, number of employees.

Sample table: employees


Sample table: department


Sample Solution:

SELECT d.dep_name,
       count(*)
FROM employees e,
     department d
WHERE e.dep_id = d.dep_id
GROUP BY d.dep_name
HAVING count(*) >= 2;

Sample Output:

 dep_name  | count
-----------+-------
 FINANCE   |     3
 MARKETING |     6
 AUDIT     |     5
(3 rows)s

Relational Algebra Expression:

Relational Algebra Expression: List the name of departments where atleast 2 employees are working in that department.

Relational Algebra Tree:

Relational Algebra Tree: List the name of departments where atleast 2 employees are working in that department.

Practice Online


Sample Database: employee

employee database structure

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Previous: From the following table, write a SQL query to find those departments where less than four employees work. Return department ID, number of employees.
Next: From the following table, write a SQL query to check whether the employees ID are unique or not. Return employee id, number of employees.

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