insert into emp_manager select U.* from ( SELECT A.* FROM (SELECT e.emp_no AS employee_ID, de.dept_no as department_code, (select emp_no FROM dept_manager WHERE emp_no = 110022) AS manager_ID FROM employees e JOIN dept_emp de ON e.emp_no = de.emp_no WHERE e.emp_no BETWEEN 10000 AND 10020) AS A union SELECT B.* FROM (SELECT e.emp_no AS employee_ID, de.dept_no AS department_code, (SELECT emp_no FROM dept_manager WHERE emp_no = 110039) AS manager_ID FROM employees e JOIN dept_emp de ON e.emp_no = de.emp_no WHERE e.emp_no BETWEEN 10021 AND 10040) AS B union SELECT C.* FROM (SELECT e.emp_no AS employee_ID, de.dept_no AS department_code, (SELECT emp_no FROM dept_manager WHERE emp_no = 110039) AS manager_ID FROM employees e JOIN dept_emp de ON e.emp_no = de.emp_no WHERE e.emp_no = 110022) AS C union SELECT D.* FROM (SELECT e.emp_no AS employee_ID, de.dept_no AS department_code, (SELECT emp_no FROM dept_manager WHERE emp_no = 110022) AS manager_ID FROM employees e JOIN dept_emp de ON e.emp_no = de.emp_no WHERE e.emp_no = 110039) AS D) as U;

For some reason, I get a return of 46 rows when I execute your query. I suggest going through the code line by line and comparing it with the attached solution from 365. Maybe execute the query each time you make a change to match the solution so you can see exactly where the issue was. That is what I did to troubleshoot my own answer. I used the TRUNCATE command in between attempts since each time you execute, it adds more rows. Good luck!

Hi Yahia! Thanks for reaching out. You should use the GROUP BY clause. Please, use the following code: INSERT INTO emp_manager SELECT u.* FROM (SELECT a.* FROM (SELECT e.emp_no AS employee_ID, MIN(de.dept_no) AS department_code, (SELECT emp_no FROM dept_manager WHERE emp_no = 110022) AS manager_ID FROM employees e JOIN dept_emp de ON e.emp_no = de.emp_no WHERE e.emp_no <= 10020 GROUP BY e.emp_no ORDER BY e.emp_no) AS a UNION SELECT b.* FROM (SELECT e.emp_no AS employee_ID, MIN(de.dept_no) AS department_code, (SELECT emp_no FROM dept_manager WHERE emp_no = 110039) AS manager_ID FROM employees e JOIN dept_emp de ON e.emp_no = de.emp_no WHERE e.emp_no > 10020 GROUP BY e.emp_no ORDER BY e.emp_no LIMIT 20) AS b UNION SELECT c.* FROM (SELECT e.emp_no AS employee_ID, MIN(de.dept_no) AS department_code, (SELECT emp_no FROM dept_manager WHERE emp_no = 110039) AS manager_ID FROM employees e JOIN dept_emp de ON e.emp_no = de.emp_no WHERE e.emp_no = 110022 GROUP BY e.emp_no) AS c UNION SELECT d.* FROM (SELECT e.emp_no AS employee_ID, MIN(de.dept_no) AS department_code, (SELECT emp_no FROM dept_manager WHERE emp_no = 110022) AS manager_ID FROM employees e JOIN dept_emp de ON e.emp_no = de.emp_no WHERE e.emp_no = 110039 GROUP BY e.emp_no) AS d) as u; Hope this helps. Best, Tsvetelin