“A little man often casts a long shadow."Italian Proverb
This query is very simple and easy to understand. It uses an IN List to find all Employees who are in Dept_No 100 or Dept_No 200.
What is going on with this IN List? Why in the world are their duplicates in there? Will this query even work? What will the result set look like? Turn the page!
Duplicate values are ignored here. We got the same ...