rand() is not random by row

[masahide.miura]

Hi,

I found that rand() function does not reply random value.
When I used it, all rows are same values through all rows.

You can see this result with bellow query:
  select *, rand() from sys.boot limit 10


ver: 1.3.0
client: Web( drillhost:8047 )
environment: distributed on EMR

Thanks.

-- 
Miura, Masahide