In response to Ivan Sergio Borgonovo : > I've a web application. > > I'm logging data related to the landing page and subsequent selected > hits. > > create table track_hit ( > hitid serial not null, > /* pk? I don't mind if serial wrap around > pk could be (hitid, tracking_time) */ > esid varchar(32), -- related to session > tracking_time timestamp not null default now(), > -- some other stats > -- first_hit boolean not null default false, -- ??? > ); > > I'd like to be sure I just count one "first hit" in a session (same > esid) in an efficient way that means I'd like to mark them with a select distinct on (esid) esid, tracking_time from track_hit order by esid, tracking_time; returns only one record for each esid, ordered by tracking_time. Should work with 8.x, maybe sice 7.x (I'm not sure) HTH, Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG: 0x31720C99, 1006 CCB4 A326 1D42 6431 2EB0 389D 1DC2 3172 0C99 -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
