If it needs to be unique, why does it need to be random?

Would a sequential (identity) number accomplish what you need?

If it truly needs to be both random and unique, you may want to pre-generate the numbers, then use an identity field to link to them:

create table RandomNumbers (

ID int primary key,

Number int)

go

;with

CTE1 (Number) as

(select abs(checksum(newid()))/100

from common.dbo.bignumbers bn1,

common.dbo.bignumbers bn2),

CTE2 (Number) as

(select distinct number

from cte1)

insert into dbo.randomnumbers (id, number)

select row_number() over (order by newid()), number

from cte2

Then, put an identity column in your table where you need a random number, and join it to the RandomNumbers table to get your random number.

On my desktop computer, this took about 10 seconds to generate about 1-million unique, random numbers.