On Sat, Oct 4, 2008 at 6:06 PM, Gregory Stark <[EMAIL PROTECTED]>wrote:
> "Gurjeet Singh" <[EMAIL PROTECTED]> writes: > > > On Sat, Oct 4, 2008 at 8:49 AM, Tom Lane <[EMAIL PROTECTED]> wrote: > > > >> "Gurjeet Singh" <[EMAIL PROTECTED]> writes: > >> > Shouldn't PG make all efforts to not execute something when the result > is > >> > already known? > >> > >> Not if said effort would cost more than is saved, which would be by far > >> the most likely result if we tried to cache all function results. > >> > > > > Sorry Tom, I confused STABLE with IMMUTABLE; my bad. > > No, this is equally untrue for immutable. Yup... I realized that after a bit of more testing after the mail... Immutable functions are single-call-per-command only of you are passing constants-only as parameters; if we have an expression involving columns, then they will be called for every row. Best regards, -- [EMAIL PROTECTED] [EMAIL PROTECTED] gmail | hotmail | indiatimes | yahoo }.com EnterpriseDB http://www.enterprisedb.com Mail sent from my BlackLaptop device
