Hi,

>>
select sys(2015) as SortOrder,* from ac ;
order by 1 descending
>>

Repeated calls to SYS(2015) won't give a random sequence.

Can you use something on the lines of:

INDEX ON RAND() TAG idx_rand
SET ORDER TO idx_rand
LOCATE
COPY NEXT 4500 TO ....

HTH,
Viv