--------------------------------------------------------

-- Actual code to UPDATE

--------------------------------------------------------

;with

A as (

select

number,

row_number() OVER(PARTITION BY tekst, number ORDER BY (SELECT NULL)) volgnr

from sb_dupli

)

update A set number=number*100+volgnr where volgnr > 1

--------------------------------------------------------

-- End Actual code to UPDATE

--------------------------------------------------------

Rereading the question, you wanted an update, above an example of an update. Offcourse you have to come up with your own update strategy.

If the range is not know you could go for negative numbers for example:

set number = - (volgnr*100 +number)

This assumes you do not have more than 99 doubles.

Ben