create procedure ZZZ_GET_RAND (
    A_LIM integer)
returns (
    ROW_NUM integer,
    RND_VAL integer)
as
declare variable V_MAX_ID integer;
declare variable V_RND integer;
begin
select max(id) from zzz_test_tab into :v_max_id;
for
  with
  nx as(
    select  0  i from rdb$database union all
    select  1  from rdb$database union all
    select  2  from rdb$database union all
    select  3  from rdb$database union all
    select  4  from rdb$database union all
    select  5  from rdb$database union all
    select  6  from rdb$database union all
    select  7  from rdb$database union all
    select  8  from rdb$database union all
    select  9  from rdb$database
  )
  ,n as(
    select t.i+ 1  i, cast(rand()*:v_max_id as int) r
    from(select n4.i* 10000 + n3.i* 1000 +n2.i* 100 +n1.i* 10 +n0.i i from nx n4, nx n3, nx n2,nx n1,nx n0
    ) t
    where t.i<=:a_lim
  )
select n.i, n.r
  from n
into
  :row_num,
  :rnd_val
do
  suspend;
end

select first  150   t.id
from ZZZ_GET_RAND( 100000 ) zzz
join zzz_test_tab t on zzz.rnd_val=t.id

------ Performance info ------
Prepare time = 0ms
Execute time = 1s 297ms
Avg fetch time = 43,23 ms

select ( 10-0.5 ) +  rand() * (  13+0.5  - ( 10-0.5 ) ) from rdb$database