Q:

concerning UNION and JOIN in mysql

Here is my tables:

how to do I get the following from the above table in mysql using union?

here is my answer:
   SELECT name, city(Person) FROM Persons
   UNION 
   SELECT name, 'something' FROM Persons
   UION
   SELECT pname, city(Project) FROM  Projects;

A:

Try something like this:
SELECT name, city, 'Person' AS Explanation FROM Persons
UNION ALL
SELECT pname, place, 'Project' AS Explanation FROM Projects

