SQL Select - Is this logic valid?

Question

Hello guys,
I was wondering if anyone can tell me if my query is valid or not? [This is an exercice, it's not something really critical].
Let suppose I have 2 tables (Organizations and Employees). I would like to retrieve all the organizations with only one fake person under.
CREATE TABLE ORGANIZATIONS
  id_organization number(10) primary key,
  name            varchar2(100) not null
CREATE TABLE EMPLOYEES
  id_employee     number(10) primary key,
  id_organization number(10),
  name            varchar2(100) not null,
  is_fake         char(1)
insert into organizations values(1, 'Org 1');
insert into organizations values(2, 'Org 2');
insert into employees values(1, 1, 'Emp 1', 1);
insert into employees values(2, 1, 'Emp 2', 0);
insert into employees values(3, 1, 'Emp 3', 0);Is this query correct ?
I mean, does this query returns the correct result? All the organization with only one fake person under?
    SELECT a.id_organization, b.id_employee
      FROM ORGANIZATIONS a
      LEFT JOIN EMPLOYEES b ON a.id_organization = b.id_organization
     WHERE b.is_fake = 1;Thanks,

Answer 1

Hi,
Thanks for posting the sample data in such a useful form!
Don't forget to post the results you want from that data.
Does your problem cioncern finidng out if there is exactly one fake in a given organization, as there is in id_organization=1? If so, maybe you should add some more data so you can compare results with an organization that has more than one fake employee, like this:
insert into employees (id_employee,     id_organization,     name,          is_fake)
     values           (21,           2,                'Fake 21',      '1');
insert into employees (id_employee,     id_organization,     name,          is_fake)
     values           (22,           2,                'Fake 22',      '1');
insert into employees (id_employee,     id_organization,     name,          is_fake)
     values           (23,           2,                'Real 23',      '0');If someone posts a solution, and it doesn't work, point out exactly where it is wrong, and explain how you get the right results in those places.
What is wrong with Karthick's solution?