sql - What does this query means? -


there table named employee , it's have employee_id, manager_id, salary columns on it. query 

select employee_id,salary,last_name employees m exists  (select employee_id employees w (w.manager_id = m.employee_id) , w.salary>10000) order employee_id asc

what query means?

a)all managers whom salaries greater 10000

b)all managers whom have @ least 1 employee making greater 10000

if subquery returns rows @ all, exists subquery true, , not exists subquery false. example:

select column1 t1 exists (select * t2);

traditionally, exists subquery starts select *, begin select 5 or select column1 or @ all. mysql ignores select list in such subquery, makes no difference.

in case option b correct.


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