select
case when seria_pl is null or seria_pl ='' then 'a' end as seria_pl,   
count(*), min(nomer_pl), max(nomer_pl) 
from put_list 
where dat_close between '2008-08-26' and '2008-09-18'
group by seria_pl

begin
select
case when seria_pl is null or seria_pl ='' then 'a' else seria_pl end as seria_pl,   
nomer_pl
into tt
from put_list 
where dat_close between '2008-08-26' and '2008-09-18'

select seria_pl, count(*) as cn, min(nomer_pl) as min_n, max(nomer_pl) as max_n from tt
group by seria_pl

drop table tt
end