TLDR; I would like to get a warning on changing/adding a foreign key for Postgresql that it locks the table and if the table is large, it could be locked for some time. When adding or changing a ...

-- 16. Write a MySQL query to create a table employees including columns employee_id, first_name, last_name, email, phone_number hire_date, job_id, salary, commission, manager_id and department_id and ...