Hi Maarten

Not sure if this is what you want, but you could try

;with testdata as(

select *

from (values ('=KET+N.207-13-F4001'),('=KET+DG014-13-F4011'),('=KET+RE002-36-MV009')) as MD (value)

)

select value

,case

when substring(value,16,1) like '[0-9]' then

substring(value,15,2)

else

substring(value,15,1)

end as groupno

from testdata