On Wed, May 16, 2012 at 4:53 PM, <seiliki@xxxxxxxxxxxxx> wrote: > Hi! I am trying to implement a mechanism to reserve the last row for every distinct value in column "c1". Take a step back. Why are you needing to preserve these rows? This smells like a likely target for normalization. Put your unique values for c1 into a separate table, along with all data that depends only on that, and reference it in your main table with a foreign key. Even if you remove all the entries from your main that reference a row, the other table will retain its data. Chris Angelico -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general