V Sh.

SELECT person.*
FROM person
LEFT JOIN sms ON sms.id = person.id
WHERE sms.id IS NULL

SELECT id_chief, SUM(salary) - MaxSalaryToDepartments as diff
FROM employee
GROUP BY id_chief
HAVING SUM(salary) > MaxSalaryToDepartments

buffer = makeBuffer();
makeBuffer() = function(piece);
buffer('blah-blah-blah') = makeBuffer()('blah-blah-blah') = function('blah-blah-blah');

select t1.metric_type, t1.state, (t2.date_change - t1.date_change) as diff
from
(
select rownum as n, metric_type, state, date_change
from
(
select *
from someTable
order by metric_type, date_change
)) t1
left join (select rownum as n, metric_type, state, date_change
from
(
select *
from someTable
order by metric_type, date_change
)) t2 on (t1.n = t2.n+1 and t1.metric_type = t2.metric_type)