I am using a query like this to try and normalize a table. WITH nd as (select * from sales order by id limit 100), people_update as (update people p set first_name = nd.first_name from nd where p.email = nd.email returning nd.id), insert into people (first_name, email, created_at, updated_at) select first_name, email , now(), now() from nd left join people_update using(id) where people_update.id is null), This works pretty good except for when the top 100 records have duplicated email address (two sales for the same email address). I am wondering what the best strategy is for dealing with this scenario. Doing the records one at a time would work but obviously it would be much slower. There are no other columns I can rely on to make the record more unique either. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general