Как выбрать данные за максимальную дату

[moroz11]

Запрос

select distinct p.t,t.kk,t.rt,t.date
		from tab t
		join (
		  select 1 t, 1 d1, 10 d2 from tab
		  union all
		  select 2 t, 11 d1, 20 d2 from tab
		  union all
		  select 3 t, 21 d1, 31 d2 from tab) p on extract(day from t.date) between p.d1 and p.d2
		where date between '2012-08-01' and '2012-08-14' and stat='1'

t kk rt date
1 0 0 2012-08-01
1 210 7,5 2012-08-02
1 210 7,5 2012-08-03
1 210 7,5 2012-08-04
1 210 7,5 2012-08-05
1 210 7,5 2012-08-06
1 210 7,5 2012-08-07
1 210 8,8 2012-08-08
1 210 8,8 2012-08-09
1 210 8,8 2012-08-10
2 200 8,8 2012-08-11
2 200 8,8 2012-08-12
2 200 8,8 2012-08-13
2 200 8,8 2012-08-14

Мне надо из этого запроса выбрать данные за максимальную дату каждой декады месяца,т.е. у меня должны в запросе остаться только 2 строки (за 10 и 14 августа):

1 210 8,8 2012-08-10
2 200 8,8 2012-08-14

Спасибо.

[Stilet]

select distinct p.t,t.kk,t.rt,t.date
		from tab t
		join (
		  select 1 t, 1 d1, 10 d2 from tab
		  union all
		  select 2 t, 11 d1, 20 d2 from tab
		  union all
		  select 3 t, 21 d1, 31 d2 from tab) p on extract(day from t.date) between p.d1 and p.d2
		where date between '2012-08-01' and '2012-08-14' and stat='1'
 and (year(date)=(select max(year(date)) from tab))
 and (month(date)=(select max(month(date)) from tab where year(date)=max(year(date))))
 and (day(date) % 10 = 1)
 or (date=(select max(date) from tab))

Как-то так...
Особо не разбирался, проверять нечего.

[evg_m]

select p.t,t.kk,t.rt,t.date
from t
inner join ( select 1 as t,  1 as d1, 10 as d2, max(day) as maxday from table where day beetwen '2012-08-01' and '2012-08-10'  and stat=1
       union select 2 as t, 11 as d1, 20 as d2, max(day) as maxday from table where day beetwen '2012-08-11' and '2012-08-20' and stat=1
       union select 3 as t, 21 as d1, 31 as d2, max(day) as maxday from table where day beetwen '2012-08-21' and '2012-08-31' and stat=1
          ) as p on t.day =p.maxday
where day beetwen '2012-08-01' and '2012-08-14'