Hi, I am not sure if it is bullet proof, but could be good starting point. Maybe someone else could find better solution:
CREATE OR REPLACE FUNCTION myschema."doCheckChanges"() RETURNS trigger AS $BODY$ DECLARE v_match_array BOOLEAN[]; v_match BOOLEAN; v_row RECORD; BEGIN FOR v_row IN SELECT attname FROM pg_attribute WHERE attrelid = (quote_ident(TG_TABLE_SCHEMA) || '.' || quote_ident(TG_TABLE_NAME))::text::regclass AND attnum > 0 ORDER BY attnum LOOP EXECUTE 'SELECT NOT ($1.' || quote_ident(v_row.attname) || ' = $2.' || quote_ident(v_row.attname) || ')' INTO v_match USING NEW, OLD; v_match_array = array_append (v_match_array, v_match); END LOOP; RAISE NOTICE 'array: %', (array_to_string(v_match_array, ',')); RETURN NEW; END; $BODY$ LANGUAGE plpgsql SECURITY DEFINER assumption: this is on update trigger function - You could extend this code to check trigger conditions and do what You want to do with v_match_array. Regards, Bartek 2012/7/3 <david.sahag...@emc.com> > > I would like another TG_* special variable to be available to a PL/pgSQL > trigger-function. > > TG_COLUMNS_UPDATED > > Its value would be NULL unless: TG_OP == ' UPDATE' and TG_LEVEL == 'ROW' > > Data type == varbit > One bit for each column of the table that the trigger is created on. > 1 means that the column was in the set clause of the update statement > that made the trigger fire > 0 means it was not > > I understand that CREATE TRIGGER already has > UPDATE [ OF column_name [, ... ] ] > > > Is this a relatively straightforward enhancement ? > > It would allow me to know whether various timestamp columns in the row > were > unlucky enough to have been set to the same exact value already existing > in the table > *versus* were simply not set by the UPDATE statement. > > Thanks, > -dvs- > > >
