2011/9/1 Merlin Moncure <mmoncure@xxxxxxxxx>: > 2011/9/1 Grzegorz Jaśkiewicz <gryzman@xxxxxxxxx>: >> On Thu, Sep 1, 2011 at 11:14 AM, Sim Zacks <sim@xxxxxxxxxxxxxx> wrote: >>> On 09/01/2011 12:26 PM, Pavel Stehule wrote: >>>> >>>> Hello >>>> >>>> postgres=# create table tt(a int, b varchar); >>>> CREATE TABLE >>>> postgres=# insert into tt values(10,'hello'); >>>> INSERT 0 1 >>>> >>>> postgres=# select md5(array_to_string(array_agg(md5(tt::text)),'')) from >> I do that as well, but it might have questionable performance when >> your table has 16M rows, and is 50GB + > > you need order by for that to work. I would do it like this: > select md5(array(select foo from foo order by foo_pkey)::text); > > it's great quick'n'dirty, but not much scalable beyond millions. I've always liked doing this with my pager: [robert@client-168] export PAGER=md5 -=[11:40:25 Thu Sep 01]=---=[ pagila-0.10.1 ]=- [robert@client-168] psql -hlocalhost -dpagila psql (9.0.4, server 9.1beta3) WARNING: psql version 9.0, server version 9.1. Some psql features might not work. Type "help" for help. pagila=# select * from actor order by actor_id; f381ebdefe0aada9c0bc14e657962c1f Robert Treat conjecture: xzilla.net consulting: omniti.com -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general