Sorry forgot to mention later try CREATE UNIQUE INDEX visit_idx ON visit_buffer( id_session, id_story ,myextract(created_on)); best regards > Louis > > what if you create one "wrapper" function > immutable? > some thing like this. > > CREATE OR REPLACE FUNCTION myextract(timestamp ) > RETURNS date AS > $BODY$ > BEGIN > return extract(date from $1) ; > END; > $BODY$ > LANGUAGE 'plpgsql' IMMUTABLE > > best regards > mdc > > > > > --- Louis-David Mitterrand > <vindex+lists-pgsql-general@xxxxxxxxxxx> escribió: > > > Hi, > > > > To constraint unique'ness of my visitors to a 24h > > periode I tried > > created a index including the 'date' part of the > > created_on timestamp: > > > > CREATE UNIQUE INDEX visit_idx ON visit_buffer > USING > > btree (id_session, > > id_story, created_on::date); > > > > psql:visit_pkey.sql:5: ERROR: syntax error at or > > near "::" > > LINE 1: ...buffer USING btree (id_session, > > id_story, created_on::date); > > > > and this: > > > > CREATE UNIQUE INDEX visit_idx ON visit_buffer > USING > > btree (id_session, id_story, extract(date from > > created_on)); > > psql:visit_pkey.sql:4: ERROR: functions in index > > expression must be marked IMMUTABLE > > > > How can I achieve what I am trying? > > > > Thanks, > > > > ---------------------------(end of > > broadcast)--------------------------- > > TIP 6: explain analyze is your friend > > > > > > Yahoo! Encuentros. > > Ahora encontrar pareja es mucho más fácil, probá el > nuevo Yahoo! Encuentros > http://yahoo.cupidovirtual.com/servlet/NewRegistration > Tarjeta de crédito Yahoo! de Banco Supervielle. Solicitá tu nueva Tarjeta de crédito. De tu PC directo a tu casa. www.tuprimeratarjeta.com.ar ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
