Hi Lynn

I have added a group by clause on the end like so which seems to work

insert into RefTable(software_name_raw,software_name_amended)

select

bt.software_name_raw,

'Needs Updating'

from

BigTable bt

where

not exists (select 1 from RefTable rf where rf.software_name_raw = bt.software_name_raw)

group by bt.software_name_raw;

would you agree that this works and we can close the case

thanks

Alan