SELECT 
    pp.phone_code, pp.price, t.id, t.phone
FROM
    call_task t
join
    provider_price pp ON (t.phone like concat(pp.phone_code, '%'))
where
    t.created_at > '2013-12-01'
        and t.id = 6666
	-- and pp.phone_code = max(pp.phone_code) // Error Code: 1111. Invalid use of group function	0,000 sec

-- group by t.id
order by t.id desc , pp.phone_code desc

select
 tt.*,
(SELECT 
    pp.phone_code -- , pp.price, t.id, t.phone
FROM
    call_task t
join
    provider_price pp ON (t.phone like concat(pp.phone_code, '%'))
where
  /*  t.created_at > '2013-12-01'
         and
*/ t.id = tt.id
	-- and pp.phone_code = max(pp.phone_code)
-- group by t.id
order by pp.phone_code desc
limit 1) as pr
from call_task tt
where
    tt.created_at > '2014-01-01'