Richard ~ Thanks for your response.
Can a trigger be written on a *view*? I can't find anything in the PostgreSQL docs that answers this question. I originally wrote these actions (described in my original message) as a trigger on my base table, but then realized I was getting in deeper and deeper trouble because (a) I was getting into cascading triggers that I didn't want and (b) I need to enable some queries to access the base table without triggering these actions. That's why I set up the view, and then I assumed that the only way I could implement these actions was as rules. ~ Ken > -----Original Message----- > From: Richard Huxton [mailto:[EMAIL PROTECTED] > Sent: Monday, December 19, 2005 4:08 AM > To: Ken Winter > Cc: 'PostgreSQL pg-sql list' > Subject: Re: [SQL] Rule causes baffling error > > Ken Winter wrote: > > This rule is supposed to (1) cause an update directed to the view > > "my_data_now" to be made to the underlying table "my_data", (2) reset > the > > "effective_date_and_time" of that row to 'now', (3) insert a record > > containing the old values into "my_data", and (4) expire that "old" > record > > by setting its "expiration_date_and_time" to 'now'. > > I think you want a trigger rather than a rule. > > Rules rewrite the query structure, triggers let you deal with values on > a row-by-row basis (for row-level triggers). > > -- > Richard Huxton > Archonet Ltd ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
