How to use join query?

Question

I need real time scenario

Answer 1

Users who lives in New York:

select full_name from account as ac, address as ad where ac.id=ad.account_id and ad.city='New York';

Select users whose city is unknown:

select full_name from account as ac left outer join address as ad on (ac.id=ad.account_id) where ad.city is null;

Answer 2

Thank you