EXISTS and NOT EXISTS in correlated subqueries in MySQL

 

 Exists :Table2 id exists in table1 so it will fetch data from table1

select * from table1 a where exists  (select distinct  b.Emp_id from table2 b
where a.emp_id=b.Emp_id ) ;

 

Not exists : emp_id is not exists from table1 i will return only not exists in table2 

select * from table1 a where not exists (select distinct  b.Emp_id from table2 b
where a.emp_id=b.Emp_id ) ;